Answer:
[tex]\frac{dy}{dt}=k(y_t-R)[/tex]
Explanation:
According to Newton’s law of cooling, the rate of loss of heat from a body and the difference in the temperature of the body and its surroundings are proportional to each other.
[tex]\frac{dy}{dt}=k(y_t-R)[/tex]
Here, [tex]y_t[/tex] represents temperature at time t, R as the room temperature, t as the independent variable, y as the dependent variable.
The equation that represents Newton's Law of Cooling for this particular situation is dy/dt = k(yt-R)
What is Newton’s law?
According to Newton’s law of cooling refer, the rate of loss of heat from a body and also the difference in the temperature of the body and also its surroundings are proportional to each other.
dy/dt is = k(yt-R)
Therefore, yt conveys temperature at time t, R as the room temperature, t as the independent variable, y as the dependent variable.
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You are working in an optical research laboratory. Your supervisor needs you to set up a doubleslit apparatus for a presentation that will provide a vertically varying pattern of red light of wavelength 693 nm on a screen. The screen of width 4.75 m at the front of the presentation room must have red fringes on either end and 21 additional red fringes between those on the end. The separation between the slits in the double slit you will use at the back of the room is 65.0 µm.
You need to determine how far away from the slits (in m) the screen must be placed. (Assume the central maximum is at the center of the screen.)
To determine the distance between the slits and the screen, we can use the formula for the separation between fringes in a double-slit interference pattern. Applying the small angle approximation, we find that the screen must be placed approximately 1.065 km away from the slits.
Explanation:To determine the distance between the slits and the screen, we can use the formula for the separation between fringes in a double-slit interference pattern:
d*sin(theta) = m*lambda
Where d is the separation between the slits (65.0 µm), lambda is the wavelength of light (693 nm), m is the order of the fringe (in this case, m = 21), and theta is the angle of the fringe from the central maximum. Since we want the central maximum to be at the center of the screen, we can consider the angle to be very small, and therefore sin(theta) ≈ theta. Rearranging the formula, we have:
theta = m*lambda / d = 21 * (693e-9 m) / (65.0e-6 m) = 2.241e-3 radians
Next, we can use the small angle approximation to find the distance from the slits to the screen. This approximation states that tan(theta) ≈ theta for small angles. Therefore, tan(theta) = y / L, where y is the distance between the center of the screen and the fringe, and L is the distance between the slits and the screen. Solving for L, we have:
L = y / tan(theta) = (4.75 m / 2) / tan(2.241e-3 radians) ≈ 1.065 km
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Suppose you defined ""positive"" motion as motion westward. What would be the persons total velocity?
Answer: I think that you are asking about an interactive reader which talks about an exercise which asked for the person's velocity who were on the bus.
The answer is 14 m/s
Explanation: When you have to do an exercise about velocity, you can do this exercise knowing the velocity from the bus in relative the street and you ALWAYS have to define your positive or negative motion about the direction in which the person were walking to know if you have to add or subtract
In this case, the bus were travelling east at 15 m/s and the person walked toward the back of the bus at 1 m/s.
It doesn't matter if the positive is the west or the east. While you only know the positive and knowing that the person was walking toward back the bus you can deduce this:
The person's total velocity is (+15 m/s) - (+1 m/s) = +14 m/s
If positive motion is defined as motion westward, the total velocity would be the individual's speed in the westward direction. It includes both the speed and the direction, which makes velocity a vector quantity.
Explanation:In the context of the question, if positive motion is defined as motion westward, then the individual's total velocity would be their speed in the westward direction with the magnitude and direction incorporated. Velocity is a vector quantity because it encompasses both magnitude (how fast an object is moving) and direction (where it is going). So if the person is walking at a speed of 3 km/h, in the westward (positive) direction, then we can say the person's total velocity is 3 km/h west.
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A fan is designed to last for a certain time before it will have to be replaced (planned obsolescence). The fan only has one speed (at a maximum of 700 rpm), and it reaches the speed in 4.0 s (starting from rest). It takes the fan 11.0 s for the blade to stop once it is turned off. The manufacturer specifies that the fan will operate up to 1 billion rotations. Andre lives in a hot climate, works outside of the home from approximately 8:00 am to 5:00 pm, Monday through Friday, does not own an air conditioner, and can't sleep with the fan running. Estimate how many hot days ????hot Andre will be able to use the fan, rounded to the nearest day. ????hot= days
Answer:
1355 days
Explanation:
Find the given attachment
Andre will not be able to use the fan at all during his working hours.
Explanation:To estimate how many hot days Andre will be able to use the fan, we need to calculate the number of rotations the fan will make during his working hours and subtract the number of rotations it takes for the fan to stop once turned off. We know that the fan reaches a speed of 700 rpm in 4.0 s from rest. This means its angular velocity is 700 * 2π/60 = 73.33 rad/s. So, in 8 hours (Andre's working hours), the fan will rotate for 73.33 * 3600 * 8 = 210,624 rotations. Subtracting the rotations it takes for the fan to stop (700 * 11 = 7700 rotations), Andre will be able to use the fan for approximately 210,624 - 7700 = 202,924 rotations. Since the fan is specified to operate up to 1 billion rotations, Andre will be able to use the fan for approximately 202,924 / 1,000,000,000 = 0.0002029 (or about 0.02%) of its lifespan. Rounded to the nearest day, this is 0 days.
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A solid sphere of uniform density has a mass of 3.0 × 104 kg and a radius of 1.0 m. What is the magnitude of the gravitational force due to the sphere on a particle of mass 9.3 kg located at a distance of (a) 1.4 m and (b) 0.21 m from the center of the sphere? (c) Write a general expression for the magnitude of the gravitational force on the particle at a distance r ≤ 1.0 m from the center of the sphere.
The gravitational force on a particle due to a sphere can be calculated using Newton's Law of gravitation. Different distances result in different force magnitudes.
Explanation:The magnitude of the gravitational force (F) on a particle due to a sphere can be calculated by using Newton's Law of Gravitation, F = G*(m1*m2)/r², where G is the gravitational constant (6.67 × 10-¹¹ N·m²/kg²), m1 and m2 are the masses of the two bodies, and r is the distance between their centers.
(a) For a distance of 1.4 m, F = G*(3.0 × 10⁴ kg*9.3 kg) / (1.4 m)².
(b) For a distance of 0.21 m, F = G*(3.0 × 10⁴ kg*9.3 kg) / (0.21 m)².
(c) For a general expression for the magnitude of the gravitational force on the particle at a distance r ≤ 1.0 m from the center of the sphere, the formula changes to F = G*(m1*m2)/r², where r ≤ 1.0 m.
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What should Jaime do to increase the number of energy storage molecules that producers can make? You may choose more than one answer.
Decrease the amount of carbon dioxide in the ecosystem.
Increase the amount of carbon dioxide in the ecosystem.
Decrease the amount of sunlight in the ecosystem.
Increase the amount of sunlight in the ecosystem.
Answer:
Decrease the amount of carbon dioxide in the ecosystem.
Explanation:
becaus egthy
To increase the number of energy storage molecules that producers can make, Jaime should:
1. Increase the amount of sunlight in the ecosystem: Sunlight is a vital source of energy for photosynthesis, the process by which producers convert carbon dioxide and water into energy-rich molecules such as glucose. More sunlight can potentially increase the rate of photosynthesis, leading to more energy storage molecules being produced.
2. Decrease the amount of carbon dioxide in the ecosystem: While carbon dioxide is essential for photosynthesis, excessive levels can inhibit the process. By decreasing the amount of carbon dioxide in the ecosystem to an optimal level, Jaime can ensure that producers can efficiently utilize available resources to produce energy storage molecules.
So, both increasing sunlight and decreasing carbon dioxide can contribute to increasing the number of energy storage molecules that producers can make.
A coil with an inductance of 2.3 H and a resistance of 14 Ω is suddenly connected to an ideal battery with ε = 100 V. At 0.13 s after the connection is made, what is the rate at which (a) energy is being stored in the magnetic field, (b) thermal energy is appearing in the resistance, and (c) energy is being delivered by the battery?
Given Information:
Resistance = R = 14 Ω
Inductance = L = 2.3 H
voltage = V = 100 V
time = t = 0.13 s
Required Information:
(a) energy is being stored in the magnetic field
(b) thermal energy is appearing in the resistance
(c) energy is being delivered by the battery?
Answer:
(a) energy is being stored in the magnetic field ≈ 219 watts
(b) thermal energy is appearing in the resistance ≈ 267 watts
(c) energy is being delivered by the battery ≈ 481 watts
Explanation:
The energy stored in the inductor is given by
[tex]U = \frac{1}{2} Li^{2}[/tex]
The rate at which the energy is being stored in the inductor is given by
[tex]\frac{dU}{dt} = Li\frac{di}{dt} \: \: \: \: eq. 1[/tex]
The current through the RL circuit is given by
[tex]i = \frac{V}{R} (1-e^{-\frac{t}{ \tau} })[/tex]
Where τ is the the time constant and is given by
[tex]\tau = \frac{L}{R}\\ \tau = \frac{2.3}{14}\\ \tau = 0.16[/tex]
[tex]i = \frac{110}{14} (1-e^{-\frac{t}{ 0.16} })\\i = 7.86(1-e^{-6.25t})\\\frac{di}{dt} = 49.125e^{-6.25t}[/tex]
Therefore, eq. 1 becomes
[tex]\frac{dU}{dt} = (2.3)(7.86(1-e^{-6.25t}))(49.125e^{-6.25t})[/tex]
At t = 0.13 seconds
[tex]\frac{dU}{dt} = (2.3) (4.37) (21.8)\\\frac{dU}{dt} = 219.11 \: watts[/tex]
(b) thermal energy is appearing in the resistance
The thermal energy is given by
[tex]P = i^{2}R\\P = (7.86(1-e^{-6.25t}))^{2} \cdot 14\\P = (4.37)^{2}\cdot 14\\P = 267.35 \: watts[/tex]
(c) energy is being delivered by the battery?
The energy delivered by battery is
[tex]P = Vi\\P = 110\cdot 4.37\\P = 481 \: watts[/tex]
An airplane is traveling at 150 m/s in level flight. In order to make a change in direction, the airplane travels in a horizontal curved path. To fly in the curved path, the pilot banks the airplane at an angle such that the lift has a horizontal component that provides the horizontal radial acceleration to move in a horizontal circular path. If the airplane is banked at an angle of 12.0 degrees, then the radius of curvature of the curved path of the airplane is
Given Information:
Velocity = v = 150 m/s
angle = θ = 12°
Required Information:
Radius of curvature = R = ?
Answer:
Radius of curvature = [tex]R = 1.079 \times 10^{4} \: m[/tex]
Explanation:
Please refer to the attached diagram,
[tex]Fcos(\theta) = m \cdot g\\Fcos(12^{\circ}) = m \cdot g \:\:\:\:\:\:eq. 1[/tex]
Where m is the mass of the plane and g is the gravitational acceleration.
[tex]Fsin(\theta) = \frac{mv^{2}}{R}\\Fsin(12^{\circ}) = \frac{m \cdot v^{2}}{R}\:\:\:\:\:\:eq. 2[/tex]
Where v is the velocity of the plane and R is the radius of curvature of the curved path of the airplane.
Dividing eq. 2 by eq. 1 yields,
[tex]tan(12^{\circ}) = \frac{v^{2}}{R\cdot g }[/tex]
[tex]since \: \frac{sin(\theta)}{cos(\theta)} = tan(\theta)[/tex]
[tex]tan(12^{\circ}) = \frac{v^{2}}{R\cdot g }\\\\R = \frac{v^{2}}{g\cdot tan(12^{\circ}) }\\\\R = \frac{150^{2}}{9.81\cdot 0.212 }\\\\R = 10793\\R = 1.079 \times 10^{4} \: m[/tex]
Therefore, the radius of curvature of the curved path of the airplane is 1.079×10⁴ m
Final answer:
The radius of curvature of an airplane's horizontal circular path can be determined by the centripetal force, provided by the horizontal component of lift when the airplane is banked at a specific angle.
Explanation:
The question involves an airplane traveling in a horizontal curved path and banking at an angle to achieve this motion. To find the radius of curvature for the airplane's path, we need to consider the centripetal force necessary for circular motion, which is supplied by the horizontal component of the lift force when the airplane is banked. The lift force itself acts perpendicular to the wings. By using trigonometry and the principles of circular motion, we can relate the banking angle, the airplane's velocity, and the force required for level flight to find the radius of curvature. Notably, this type of problem is a common application of Newton's laws of motion in a circular motion context.
Dan picks up a 15-m-long pole and begins running very fast, holding the pole horizontally and pointing in the direction he's running. He heads toward a barn that is12 m long and has open doors at each end. Dan runs so fast that, to Farmer Brown standing by his barn, the ladder is only 5 m long. As soon as the pole is completely inside the barn, Farmer Brown closes both doors so that Dan and the pole are inside with both doors shut. Then, just before Dan reaches the far door, Farmer Brown opens both doors and Dan emerges, still moving at high speed. According to Dan, however, the barn is contracted to only 4 m and the pole has its full 15 m length. Farmer Brown sees the pole completely inside the barn with both doors closed.
In the farmer's reference frame, eight events occur in the following order:
1. The front of the pole reaches the back of the barn (FB).
2. The back of the pole reaches the back of the barn (BB).
3, 4. (simultaneous events) The farmer shuts the front door (SF); the farmer shuts the back door (SB).
5. The front of the pole reaches the front of the barn (FF).
6, 7. (simultaneous events) The farmer opens the front door (OF). The farmer opens the back door (OB).
8. The back of the pole reaches the front of the barn (BF).
What does Dan see happening (in the chronological order)?
In the farmer's reference frame, eight events occur in the following order:
1. The front of the pole reaches the back of the barn (FB).
2. The back of the pole reaches the back of the barn (BB).
3, 4. (simultaneous events) The farmer shuts the front door (SF); the farmer shuts the back door (SB).
5. The front of the pole reaches the front of the barn (FF).
6, 7. (simultaneous events) The farmer opens the front door (OF). The farmer opens the back door (OB).
8. The back of the pole reaches the front of the barn (BF).
What does Dan see happening (in the chronological order)?
1. FB; 2, 3. FF and OF are simultaneous; 4. SF; 5, 6. BB and OB are simultaneous; 7. SB; 8 BF.
1. FB; 2. FF; 3, 4. SF and OF are simultaneous; 5, 6. OB and SB are simultaneous; 7. BB; 8 BF.
1. FB; 2, 3. SF and OF are simultaneous; 4. FF; 5, 6. OB and SB are simultaneous; 7. BB; 8 BF.
1. FB; 2. SF; 3, 4. FF and OF are simultaneous; 5, 6. BB and SB are simultaneous; 7. OB; 8 BF.
Answer:
1. FB; 2. SF; 3, 4. FF and OF are simultaneous; 5, 6. BB and SB are simultaneous; 7. OB; 8 BF
Explanation:
According to the report the listed below are what Dan saw in the exact chronological order.
1. FB; 2. SF; 3, 4. FF and OF are simultaneous; 5, 6. BB and SB are simultaneous; 7. OB; 8 BF
These represents the series of events as described in the question.
While a guitar string is vibrating, you gently touch the midpoint of the string to ensure that the string does not vibrate at that point. The lowest-frequency standing wave that could be present on the string vibrates at Group of answer choices a. twice the fundamental frequency. b. the fundamental frequency. c. three times the fundamental frequency. d. four times the fundamental frequency. e. There is not enough information to decide.
Answer:
Option A is correct - While a guitar string is vibrating, you gently touch the midpoint of the string to ensure that the string does not vibrate at that point. The lowest-frequency standing wave that could be present on the string vibrates at twice the fundamental frequency.
Explanation:
Before touching the midpoint of the string, the string vibrates with one loop.
Fundamental frequency, f1 = v/(2*L)
Now, when the midpoint of the guitar string was touched, the string vibrates with two loops.
Hence, f2 = 2*v/(2*L)
f2 = 2*f1
Therefore, compared to the fundamental frequency the frequency would be double.
Option A is correct - While a guitar string is vibrating, you gently touch the midpoint of the string to ensure that the string does not vibrate at that point. The lowest-frequency standing wave that could be present on the string vibrates at twice the fundamental frequency.
Summer temperatures are usually warmer than
A. winter temperatures.
B. spring temperatures.
C. autumn temperatures.
D. all of these
D _____________________________________________________
A 10-turn coil of wire having a diameter of 1.0 cm and a resistance of 0.30 Ω is in a 1.0 mT magnetic field, with the coil oriented for maximum flux. The coil is connected to an uncharged 3.0 μF capacitor rather than to a current meter. The coil is quickly pulled out of the magnetic field.
Afterward, what is the voltage across the capacitor?
Answer:
The voltage across the capacitor = 0.8723 V
Explanation:
From the question, it is said that the coil is quickly pulled out of the magnetic field. Therefore , the final magnetic flux linked to the coil is zero.
The change in magnetic flux linked to this coil is:
[tex]\delta \phi = \phi _f - \phi _i[/tex]
= 0 - BA cos 0°
[tex]\delta \phi =-BA \\ \\ \delta \phi =-B( \pi r^2) \\ \\ \delta \phi =(1.0 \ mT)[ \pi ( \frac{d}{2} )^2][/tex]
[tex]\delta \phi =(1.0 \ mT)[ \pi ( \frac{0.01}{2} )^2][/tex]
[tex]\delta \phi = -7.85*10^8 \ Wb[/tex]
Using Faraday's Law; the induced emf on N turns of coil is;
[tex]\epsilon = N |\frac{ \delta \phi}{\delta t} |[/tex]
Also; the induced current I = [tex]\frac{ \epsilon}{R}[/tex]
[tex]\frac{ \delta q}{ \delta t} = \frac{1}{R} (N|\frac{\delta \phi}{\delta t } |)[/tex]
[tex]\delta q = \frac{1}{R} N|\delta \phi |[/tex]
[tex]\delta q = \frac{1}{0.30} (10)| -7.85*10^8 \ Wb |[/tex]
[tex]\delta q = 2.617*10^{-6} \ C[/tex]
The voltage across the capacitor can now be determined as:
[tex]\delta \ V =\frac{ \delta q}{C}[/tex]
= [tex]\frac{ 2.617*10^{-6} \ C}{3.0 \ *10^{-6} F}[/tex]
= 0.8723 V
Wonder Woman and Superman fly to an altitude of 1610 km, carrying between them a chest full of jewels that they intend to put into orbit around Earth. They want to make this tempting treasure inaccessible to their evil enemies who are trying to gain possession of it, yet keep it available for themselves for future use when they retire and settle down. But perhaps the time to retire is now! They accidentally drop the chest, which leaves their weary hands at rest, and discover that they are no longer capable of catching it as it falls into the Pacific Ocean. At what speed vf does the chest impact the surface of the water? Ignore air resistance (in reality, it would make large difference). The radius and mass of Earth are 6370 km and 5.98×1024 kg, respectively
Answer:
5026.55 m/s
Explanation:
Gravitation potential of a body in orbit from the center of the earth is given as
Pg = -GM/R
Where G is the gravitational constant 6.67x10^-11 N-m^2kg^-2
M is the mass of the earth = 5.98x10^24 kg
R is the distance from that point to the center of the earth = r + Re
r is the distance above earth surface, Re is the earth's radius.
R = 1610 km + 6370 km = 7980 km
Pg = -(6.67x10^-11 x 5.98x10^24)/7980x10^3
Pg = -49983208.02 J/kg
The negative sign means that the gravitational potential is higher away from earth than it is at the earth's surface (it shows convention).
This indicates the kinetic energy per kilogram that the chest of jewel will fall with to earth.
Gravitation Potential on earth's surface is
Pg = -GM/Re
= -(6.67x10^-11 x 5.98x10^24)/6370x10^3 = -62616326.53 J/kg
Difference in gravity potential = -49983208.02 - (-62616326.53)
= 12633118.51 J/kg
The velocity V of the jewel chest will be
0.5v^2 = 12633118.51
V^2 = 25266237.02
V = 5026.55 m/s
Diesel engines give more miles per gallon than gasoline engines, but some of this is due to the higher energy content of diesel fuel. At highway speeds, it takes 0.20 MJ to move an aerodynamic car 1.0 km. At highway speeds, with a gasoline engine, a car gets 16 km per liter of fuel; with a diesel engine under the hood, the car gets 19 km per liter of fuel. One liter of diesel contains 36 MJ; 1 liter of gasoline contains only 32 MJ. Part A What is the efficiency of the diesel engine
Answer:
0.106
Explanation:
For 1 liter of diesel the car can get 19 km, if it takes 0.2 MJ for each km then it would take the total energy of 19*0.2 = 3.8 MJ to move an aerodynamic car 19 km. Since 1 liter of of diesel also contains 36 MJ in internal energy, then the efficiency of the diesel engine is the ratio of its output energy over its input energy:
[tex]\frac{3.8}{36} = 0.106[/tex]
The efficiency of a diesel engine, in the given scenario, is found to be 10.56%. This is determined by considering the energy content of diesel fuel and the amount of work done by the engine.
Explanation:Firstly, the energy content for a liter of diesel fuel is 36 MJ, and the car can travel 19 km with one liter of fuel. Thus, the total energy to travel 19 km is 19 km * 0.20 MJ/km = 3.8 MJ. The useful outcome is therefore 3.8 MJ from the total of 36 MJ. Therefore, applying the formula for efficiency which is Output Energy/Input Energy * 100%, gives a result of (3.8 MJ / 36 MJ) * 100% = 10.56%.
This indicates that the diesel engine is 10.56% efficient at converting the energy in diesel fuel into work to move the car, whereas the remaining energy is lost mainly due to heat, sound etc.
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A musician on a unicycle is riding at a steady 6.2 m/s while playing their well tuned oboe at an A above middle C (440 Hz). They then ride toward another musician sitting on a park bench also playing an A above middle C. However it appears to them that one of them is off as they hear beats. If we assume both are tuned properly and the outside temperature is 27 oC what will the beat frequency they hear be
Answer:
The frequency of the beat is [tex]f_t = 8Hz[/tex]
Explanation:
From the question we are told that
The speed of the ride [tex]v = 6,2 m/s[/tex]
The frequency of the oboe is [tex]f = 440Hz[/tex]
The temperature outside is [tex]T = 27^oC[/tex]
Generally the speed of sound generated in air is mathematically evaluated as
[tex]v_s = 331 + 0.61 T[/tex]
Substituting value
[tex]v_s = 331 + 0.61 *27[/tex]
[tex]v_s = 347.47 \ m/s[/tex]
The frequency of sound(generated by the musician on he park) getting to the musicians on the unicycle is mathematically evaluated as
[tex]f_a = \frac{v_s }{v_s - v} f[/tex]
substituting values
[tex]f_a = \frac{347.47 }{347.47 - 6.2} * 440[/tex]
[tex]f_a = 448Hz[/tex]
Since the musician on the park is not moving the frequency of sound (from the musicians riding the unicycle )getting to him is = 440Hz
The beat frequency these musician here is mathematically evaluated as
[tex]f_t = f_a - f[/tex]
So [tex]f_t = 448 - 440[/tex]
[tex]f_t = 8Hz[/tex]
A 22-turn circular coil of radius 3.00 cm and resistance 1.00 Ω is placed in a magnetic field directed perpendicular to the plane of the coil. The magnitude of the magnetic field varies in time according to the expression B = 0.010 0t + 0.040 0t2, where B is in teslas and t is in seconds. Calculate the induced emf in the coil at t = 4.60 s.
Answer:
23.5 mV
Explanation:
number of turn coil 'N' =22
radius 'r' =3.00 cm=> 0.03m
resistance = 1.00 Ω
B= 0.0100t + 0.0400t²
Time 't'= 4.60s
Note that Area'A' = πr²
The magnitude of induced EMF is given by,
lƩl =ΔφB/Δt = N (dB/dt)A
=N[d/dt (0.0100t + 0.0400 t²)A
=22(0.0100 + 0.0800(4.60))[π(0.03)²]
=0.0235
=23.5 mV
Thus, the induced emf in the coil at t = 4.60 s is 23.5 mV
Select the correct answer from each drop-down menu. Various plant and animal species are on the verge of extinction. Because all organisms are [BLANK] to their native habitat, human activities that result in [BLANK] are the major reason for their extinction.
Answer:
Because all organisms are
adapted
to their native habitat, human activities that result in
habitat destruction
are the major reason for their extinction.
Explanation:
Answer:
Adapted
and
habitat destruction
Which number multplied by nine is equal to 81?
O 7
O 8
O9
Answer:
9
Explanation:
9×9 is 81, i hope this helpes
Answer:
9
Explanation:
Your friend is trying to construct a clock for a craft show and asks you for some advice. She has decided to construct the clock with a pendulum. The pendulum will be a very thin, very light wooden bar with a thin, but heavy, brass ring fastened to one end. The length of the rod is 80 cm and the diameter of the ring is 10 cm. She is planning to drill a hole in the bar to place the axis of rotation 15 cm from one end. She wants you to tell her the period of this pendulum.
Answer:
The period of the pendulum is [tex]T = 1.68 \ sec[/tex]
Explanation:
The diagram illustrating this setup is shown on the first uploaded image
From the question we are told that
The length of the rod is [tex]L = 80 \ cm[/tex]
The diameter of the ring is [tex]d = 10 \ cm[/tex]
The distance of the hole from the one end [tex]D = 15cm[/tex]
From the diagram we see that point A is the center of the brass ring
So the length from the axis of rotation is mathematically evaluated as
[tex]AP = 80 + 10 -5 -15[/tex]
[tex]AP = 70 \ cm = \frac{70}{100} = 0.7 \ m[/tex]
Now the period of the pendulum is mathematically represented as
[tex]T = 2 \pi \sqrt{\frac{AP}{g} }[/tex]
[tex]T = 2 \pi \sqrt{\frac{0.7}{9.8 } }[/tex]
[tex]T = 1.68 \ sec[/tex]
A photoelectric experiment is performed where green light with a wavelength of 546.1 nm is shined on a metal plate, creating a photocurrent from it to a collector plate. When the potential difference between the metal plate and the collector is increased to a magnitude of 0.728 V, the photocurrent goes to zero—in other words, this is the stopping potential. What is the work function (in eV) for this metal?
Answer:
[tex]\phi=1.55 [eV][/tex]
Explanation:
We can use the work function equation for a photoelectric experiment:
[tex]\phi=\frac{hc}{\lambda}-K_{max}[/tex]
h is the plank constantc is the speed of lightλ is the wave lengthK is the kinetic energy (or K=eΔV)So we will have:
[tex]\phi=\frac{hc}{\lambda}-e\Delta V[/tex]
[tex]\phi=\frac{6.63*10^{-34}*3*10^{8}}{546.1*10^{-9}}-0.728eV[/tex]
[tex]\phi=3.64*10^{-19}[J]-0.728 [eV][/tex]
[tex]\phi=(3.64*10^{-19}[J]*\frac{1eV}{1.6*10^{-19}[J]})-0.728 [eV][/tex]
[tex]\phi=2.28 [eV] - 0.728 [eV][/tex]
[tex]\phi=1.55 [eV][/tex]
I hope it helps you!
Answer:
The work function is [tex]\phi = 1.544eV[/tex]
Explanation:
From the question we are told that
The wavelength of the green light is [tex]\lambda = 546.1nm[/tex]
The stopping potential is [tex]V= 0.728V[/tex]
At stopping potential the kinetic is also maximum because this where the electron(causing the current ) would flow at it highest speed before return to zero
So the maximum kinetic energy of this electron in term of electron volt is
[tex]KE_{max} = 0.728 eV[/tex]
This maximum kinetic energy is mathematically represented as
[tex]KE_{max} = \frac{hc}{\lambda} - \phi[/tex]
Where h is the planck's constant with a value [tex]h = 4.1357 *10^{-15} eV[/tex]
c is the speed of light [tex]c = 3.0 *10^8 m/s[/tex]
[tex]\phi[/tex] is the work function
Making [tex]\phi[/tex] the subject of the formula
[tex]\phi = \frac{hc}{\lambda} - KE_{max}[/tex]
Substituting values
[tex]\phi = \frac{4.1357 *10^{-15} * (3.0 *10^8)}{546.1 *10^{-9}} - 0.728[/tex]
[tex]\phi = 1.544eV[/tex]
Pls help ASAP. This is astronomy but there isn't an option :)
Order the hierarchy of astronomy from smallest to largest.
Universe, Galaxy, Moons, Stars, Planet
From largest to smallest they are: Universe, galaxy, solar system, star, planet, moon and asteroid.
Explanation:Let's describe them from smallest to largest. In fact the size order is not exact as there are exceptions.An asteroid is a rocky body which lies in the asteroid belt between Mars and Jupiter. They are typically quite small object. The largest asteroid Ceres has been reclassified as a dwarf planet.A moon is typically a rocky body which is in orbit around a planet. Some moons such as our Moon are quite large and are typically bigger than asteroid. Some moons can actually be smaller than some asteroids.A planet is a nearly spherical body which is in orbit around the Sun. Planets are larger than moons.A star is what planets orbit around. It is the source of light and heat. Our Sun is a star which is many times bigger than all of the planets.A solar system is a star and all of its planets, asteroids, comets and other bodies. It is significantly bigger than a star.A galaxy, such as our Milky Way Galaxy, is a collection of solar systems orbiting around a central core. Most galaxies have a supermassive black hole at their centres.Galaxies also form clusters which are large scale structures.The universe is everything. It contains billions of galaxies. Lots of information RIGHT!!!!
YOUR VERY WelCoMe!!!! :) :) :) :) :0 :)
Answer:
Universe, galaxy, solar system, star, planet, moon and asteroid. Hope this helped!
The ball rolling along a straight and level path. The ball is rolling at a constant
speed of 2.0 m/s. The mass of the ball is 3.0 kg. What is the kinetic energy of the
ball? (KE=0.5*m*v)
Answer:6 joules
Explanation:
Mass(m)=3kg
Velocity(v)=2m/s
Kinetic energy=0.5 x m x v^2
Kinetic energy=0.5 x 3 x 2^2
Kinetic energy=0.5 x 3 x 2 x 2
Kinetic energy=6
A ship is floating on a lake. Its hold is the interior space beneath its deck; the hold is empty and is open to the atmosphere. The hull has a hole in it, which is below the water line, so water leaks into the hold. The effective area of the hole is 4.8 × 10-3 m2 and is located 2.5 m beneath the surface of the lake. What volume of water per second leaks into the ship?
Answer:
33.4 litres/sec
Explanation:
Given:
hole area A = 0.0048 m²
Velocity is given by:
V =√2gh = √(2 x 9.8 x 2.5) = 7 m/sec
flow = A x V = (0.0048)(7) = 0.0334 m³/sec
0.0334 m³/sec => 33.4 litres/sec
No water leaks into the ship because the velocity of the water entering the hole is 0 m/s.
Explanation:The volume of water leaking into the ship can be calculated using Archimedes' principle, which states that the buoyant force acting on an object submerged in a fluid is equal to the weight of the fluid displaced by the object. The volume of water displaced is equal to the volume of water leaking into the ship. The formula to calculate the volume of water leaking per second is: V = A * h * v, where V is the volume, A is the area of the hole, h is the height of the water above the hole, and v is the velocity of the water entering the hole. In this case, the area of the hole is given as 4.8 × 10-3 m2, the height of the water above the hole is 2.5 m, and we can assume the velocity of the water entering the hole is 0 m/s since the ship is floating on a lake and there is no external force pushing the water into the hole.
Using the formula, we can calculate the volume of water leaking per second:
V = (4.8 × 10-3 m2) * (2.5 m) * 0 m/s = 0 m3/s
Therefore, no water is leaking into the ship because the velocity of the water entering the hole is 0 m/s.
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You are suffering through a court case arising from a recent car accident that you were in. You were traveling West, alone in your car, which has a mass of 1000 kg, through an intersection when another driver in a small car (mass 850 kg) traveling South crashed into your passenger side at the center of the intersection. The two cars became stuck together and skidded off the road. For this problem, choose the positive x-axis to point to the East (right) and the positive y-axis to point North (up). You recall that you had just looked at the speedometer before the accident and were traveling at 20 m/s. What was your initial momentum vector?
Answer:
p₀ = (- 20,000 i - 17,000 j) kg m / s
vₓ = -10.81 m / s , v_{y} = - 9,189 m / s
Explanation:
This exercise can be solved with the conservation of the moment.
The system is formed by the two cars, so the forces during the crash are internal and the moment is conserved
initial moment. Just before the crash
p₀ = M v₁ + m v₂
where the masses M = 1000 kg with a velocity of v₁ = - 20 i m / s for traveling west, the second vehicle has a mass m = 850 kg and a velocity of v₂ = - 20 i m / s, we substitute
p₀ = - 1000 20 i - 850 20 j
p₀ = (- 20,000 i - 17,000 j) kg m / s
final moment. Right after the crash
how the cars fit together
[tex]p_{f}[/tex] = (M + m) [tex]v_{f}[/tex]
the final speed is shaped
v_{f} = vₓ i + v_{y} j
we substitute
p_{f} = (M + m) (vₓ i + v_{y} j)
p_{f} = (1000 + 850) (vₓ i + [tex]v_{y}[/tex]j)
p₀ = p_{f}
(- 20000 i - 17000 j) = 1850 (vₓ i + v_{y} j)
we solve for each component
vₓ = -20000/1850
vₓ = -10.81 m / s
v_{y} = -17000/1850
v_{y} = - 9,189 m / s
A spring (k = 200 N/m) is fixed at the top of a frictionless plane inclined at angle θ = 33 °. A 1.2 kg block is projected up the plane, from an initial position that is distance d = 0.90 m from the end of the relaxed spring, with an initial kinetic energy of 29 J. (a) What is the kinetic energy of the block at the instant it has compressed the spring 0.30 m? (b) With what kinetic energy must the block be projected up the plane if it is to stop momentarily when it has compressed the spring by 0.40 m?
Answer:
Explanation:
Initial kinetic energy = 29 J
work done against gravity = mgsin33 x d , m is mass of the block
= 1.2 x 9.8 sin 33 x .9
= 5.76 J
potential energy stored in compressed spring
= 1/2 k x², k is spring constant and x is compression
= .5 x 200 x .3²
= 9
energy left = 29 - ( 5.76 + 9 )
= 14.24 J
b )
energy stored in spring when compression is .4 m
= 1/2 x 200 x .4²
= 16 J
required kinetic energy = 16 + 5.76
= 21.76 J
Block must be projected with energy of 21.76 J .
Find the magnitude of the average force ⟨Fx⟩⟨Fx⟩ in the x direction that the particle exerts on the right-hand wall of the container as it bounces back and forth. Assume that collisions between the wall and particle are elastic and that the position of the container is fixed. Be careful of the sign of your answer. Express the magnitude of the average force in terms of mmm, vxvxv_x, and LxLxL_x.
Answer:
See explaination
Explanation:
Please kindly check attachment for the step by step solution of the given problem.
The attached file has a detailed solution of the given problem.
Newton's second law allows us to find the average force for the impact of a particle against the wall of a container is:
[tex]F = \frac{m v_x^2}{L_x}[/tex]
Newton's second law is the change of the momentum with respect to time and the momentum is defined as the product of the mass and the velocity of the body.
[tex]F = \frac{dp}{dt} \\p = m v[/tex]
where F is the force, p the moment, m the mass, t the time and v is the velocity.
Ask for the average force, therefore we change the differentials for variations.
[tex]<F> = m \frac{\Delta v}{\Delta t}[/tex]
They indicate that the velocity in the direction of the wall is vₓ and the mass of the container is much greater than the mass of the particle, they also indicate that the collision is elastic, therefore the speed of the particle before and after the collision is equal , but its address changes.
Δv = vₓ - (-vₓ)
Δv = 2 vₓ
The change in velocity occurs during the collision, in the rest of the motion the particle has a constant velocity, using the uniform motion relation.
[tex]v = \frac{d}{t} \\t = \frac{d}{v}[/tex]
The particle travels a distance Lₓ from inside the container to the wall and bounces, we can find the total time for the particle where the distance of the entire route is:
d = 2 Lₓ
t = [tex]\frac{2L_x}{v_x}[/tex]
Let's substitute in Newton's second law.
[tex]<F>= \frac{m \ 2v_x}{ \frac{2L_x}{v_x} } \\<F>= \frac{m v_x^2}{L_x}[/tex]
In conclusion, using Newton's second law we can find the average force for the collision of a particle against the wall of a container is:
[tex]<F> = \frac{m \ v_x^2}{L_x}[/tex]
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Describe what would you do different in your daily routine to eat healthier.....please help me noooow
Answer:
Drink water before every meal. Guzzling a glass of water before every meal can help you lose weight, improve your skin, and feel more energized. ...
Make one of your meals healthier each day. Forget fad diets and strict healthy-eating rules. ...
Walk more. ...
Add vegetables to everything. ...
Get a good night's sleep.
Explanation:
interdependence between plants and animals
Answer:
plants depend on animals for CO2 (to use during photosynthesis) while animals depend on plants for food (consumation)
Explanation:
Answer:
plants depend on animals for CO2 (to use during photosynthesis) while animals depend on plants for food (consumation)
Explanation:
Type A.
1. (a) A rectangular frame of wire of 25 cm x 15 cm is placed
in a uniform electric field of strength 2 x 10-NC-, such
that the plane of the coil is normal to field. Find the electric
flux linked with the rectangular frame.
(6) Calculate the electric flux linked with the frame, when
it is converted into (1) a square and (ii) a circular frame.
(c) In which case is the electric flux maximum ?
O m ? C-1 (h) () SON m2 -1.
Answer:
a) 750W
b) 800W
1018.9W
c) the circular frame
Explanation:
a) To find the electric flux you use the following formula:
[tex]\Phi_E=EAcos\theta=EA[/tex]
where you have assumed that the plane of the loop and B are perpendicular between them.
By replacing you obtain:
[tex]\Phi_E=(2*10^4N/C)(0.25m)(0.15m)=750W[/tex]
b) In order to calculate the electric flux in a square frame you first calculate the perimeter of the rectangular frame of wire:
P = 0.25m+0.25m+0.15m+0.15m=0.8m
A square with this length will have sides of 0.2m
Hence. you have that the electric flux is:
[tex]\Phi_E=(2*10^4N/C)(0.2m)^2=800W[/tex]
for a circular frame you have that the radius is:
[tex]s=2\pi r\\\\r=\frac{s}{2\pi}=\frac{0.8m}{2\pi}=0.127m[/tex]
Then, the electric flux will be:
[tex]\Phi_E=(2*10^4N/C)(\pi)(0.127m)^2=1018.9W[/tex]
c) The electric flux is maximum in the circular frame.
a solenoid has an internal magnetic field of 0.28T. What is the energy density of the field?
Answer:
Energy density, [tex]E=3.11\times 10^4\ J[/tex]
Explanation:
It is given that,
Magnetic field in a solenoid is 0.28 T
We need to find the energy density of the field. The energy density of the magnetic field is given by below formula as follows :
[tex]E=\dfrac{B^2}{2\mu_o}\\\\E=\dfrac{(0.28)^2}{2\times 4\pi \times 10^{-7}}\\\\E=3.11\times 10^4\ J[/tex]
So, the energy density of this field is [tex]3.11\times 10^4\ J[/tex].
A uniform disk has a mass of 3.7 kg and a radius of 0.40 m. The disk is mounted on frictionless bearings and is used as a turntable. The turntable is initially rotating at 30 rpm. A thin-walled hollow cylinder has the same mass and radius as the disk. It is released from rest, just above the turntable, and on the same vertical axis. The hollow cylinder slips on the turntable for 0.20 s until it acquires the same final angular velocity as the turntable. What is the final angular momentum of the system
Answer:
1.25 kgm²/sec
Explanation:
Disk inertia, Jd =
Jd = 1/2 * 3.7 * 0.40² = 0.2960 kgm²
Disk angular speed =
ωd = 0.1047 * 30 = 3.1416 rad/sec
Hollow cylinder inertia =
Jc = 3.7 * 0.40² = 0.592 kgm²
Initial Kinetic Energy of the disk
Ekd = 1/2 * Jd * ωd²
Ekd = 0.148 * 9.87
Ekd = 1.4607 joule
Ekd = (Jc + 1/2*Jd) * ω²
Final angular speed =
ω² = Ekd/(Jc+1/2*Jd)
ω² = 1.4607/(0.592+0.148)
ω² = 1.4607/0.74
ω² = 1.974
ω = √1.974
ω = 1.405 rad/sec
Final angular momentum =
L = (Jd+Jc) * ω
L = 0.888 * 1.405
L = 1.25 kgm²/sec
To find the final angular momentum of the system, we can apply the principle of conservation of angular momentum. The initial angular momentum of the turntable is equal to its final angular momentum, which can be determined using the moment of inertia and final angular velocity of the system.
Explanation:The final angular momentum of the system can be determined by applying the principle of conservation of angular momentum. Since no external torques act on the system, the angular momentum of the system remains constant. Initially, the turntable has an angular momentum given by L1 = I1ω1, where I1 is the moment of inertia of the turntable and ω1 is its initial angular velocity. After the hollow cylinder slips on the turntable and acquires the same final angular velocity, the system's angular momentum becomes L2 = I1ω2. Setting L1 = L2 and solving for ω2 gives us the final angular velocity of the system. Finally, we can use the moment of inertia of the turntable to calculate its final angular momentum, Lf = I1ω2.
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