Answer:
Approximately 3 photons
Explanation:
The energy of a photon at the peak of visual sensitivity is given by:
[tex]E=\frac{hc}{\lambda}[/tex]
where
h is the Planck constant
c is the speed of light
[tex]\lambda=550 nm = 5.5\cdot 10^{-7}m[/tex] is the wavelength of the photon
Substituting into the formula,
[tex]E_1=\frac{(6.63\cdot 10^{-34} Js)(3\cdot 10^( m/s)}{5.50\cdot 10^{-7} m}=3.6\cdot 10^{-19} J[/tex]
This is the energy of one photon. The human eye can detect an amount of energy of
[tex]E=10^{-18} J[/tex]
So the amount of photons contained in this energy is
[tex]n=\frac{E}{E_1}=\frac{10^{-18} J}{3.6\cdot 10^{-19}J}=2.8 \sim 3[/tex]
so approximately 3 photons.
The four inner planets of our solar system are
The four inner planets of our solar system are Mercury, Venus, Earth, and Mars.
What is the solar system?A solar system is a group of celestial bodies, which is constituted of stars, planets, asteroids, and so on.
here,
The four inner planets of our solar system, also known as the terrestrial planets, are,
These four planets are called "terrestrial" because they are rocky and relatively small compared to the outer gas giants, such as Jupiter, Saturn, Uranus, and Neptune. They are also closer to the Sun and have shorter orbital periods than the outer planets.
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What is the potential difference across a 15 Ω resistor that has a current of 3.0 A?
Answer:
45 V
Explanation:
Use Ohm's law:
V = IR
V = (3.0 A) (15 Ω)
V = 45 V
Answer:
45V
Explanation:
R=V/I
V=I/R
V=15ohms•3.0 A
V=45V
A Ping-Pong ball moving East at a speed of 4 m/s collides with a stationary bowling ball. The Ping-Pong ball bounces back to the West, and the bowling ball moves very slowly to the East. Which object experiences the greater magnitude impulse during the collision?
Answer:
They experience the same magnitude impulse
Explanation:
We have a ping-pong ball colliding with a stationary bowling ball. According to the law of conservation of momentum, we have that the total momentum before and after the collision must be conserved:
[tex]p_i = p_f\\p_p + p_b = p'_p+p'_b[/tex]
where
[tex]p_p[/tex] is the initial momentum of the ping-poll ball
[tex]p_b[/tex] is the initial momentum of the bowling ball (which is zero, since the ball is stationary)
[tex]p'_p[/tex] is the final momentum of the ping-poll ball
[tex]p'_f[/tex] is the final momentum of the bowling ball
We can re-arrange the equation as follows
[tex]p_p - p'_p = p_b'-p_b[/tex]
or
[tex]-\Delta p_p = \Delta p_b[/tex]
which means
[tex]|\Delta p_p | = |\Delta p_b|[/tex] (1)
so the magnitude of the change in momentum of the ping-pong ball is equal to the magnitude of the change in momentum of the bowling ball.
However, we also know that the magnitude of the impulse on an object is equal to the change of momentum of the object:
[tex]I=\Delta p[/tex] (2)
Therefore, (1)+(2) tells us that the ping-pong ball and the bowling ball experiences the same magnitude impulse:
[tex]|I_p| = |I_b|[/tex]
What is an elastic collision?
Answer:
A collision in which both total momentum and total kinetic energy are conserved
Explanation:
In classical physics, we have two types of collisions:
- Elastic collision: elastic collision is a collision in which both the total momentum of the objects involved and the total kinetic energy of the objects involved are conserved
- Inelastic collision: in an inelastic collision, the total momentum of the objects involved is conserved, while the total kinetic energy is not. In this type of collisions, part of the total kinetic energy is converted into heat or other forms of energy due to the presence of frictional forces. When the objects stick together after the collision, the collisions is called 'perfectly inelastic collision'
An elastic collision is where the total kinetic energy and total momentum before and after the collision are conserved. These collisions occur without permanent deformation or energy loss in other forms. This concept is important in physics, particularly in one-dimensional collisions involving atoms.
An elastic collision is a type of collision in which the total kinetic energy and total momentum of the system are conserved. This means that the kinetic energy before the collision is equal to the kinetic energy after the collision, and there is no permanent deformation of the objects involved or conversion into other energy forms like heat or sound. Elastic collisions are particularly relevant in atomic interactions, where collisions between atoms can often be considered elastic.
In one-dimensional collisions, conservation of kinetic energy and momentum allow us to calculate the final velocities of the colliding bodies using their initial velocities and their masses. A common example of nearly elastic collisions in a macroscopic context includes collisions of steel blocks on an icy surface or carts with spring bumpers on an air track, where friction is minimal.
Which property describes the amount of energy that flows past a given area per unit of time?
A.Intensity
B.Pitch
C.Speed
D.Wavelength
it is intensity. Option A
Which shows the correct order of events after the big bang occurred? strong force separated from the unified force, inflationary expansion occurred, quarks and electrons formed, electromagnetic and weak forces separated from the unified force, gravity separated from the unified force electromagnetic and weak forces separated from the unified force, gravity separated from the unified force, strong force separated from the unified force, inflationary expansion occurred, quarks and electrons formed gravity separated from the unified force, strong force separated from the unified force, inflationary expansion occurred, electromagnetic and weak forces separated from the unified force, quarks and electrons formed quarks and electrons formed, electromagnetic and weak forces separated from the unified force, inflationary expansion occurred, strong force separated from the unified force, gravity separated from the unified force
Answer:
C) gravity separated from the unified force, strong force separated from the unified force, inflationary expansion occurred, electromagnetic and weak forces separated from the unified force, quarks and electrons formed
Gravity separated from the unified force, strong force separated from the unified force, inflationary expansion occurred, electromagnetic and weak forces separated from the unified force, quarks and electrons formed.
What is big bang theory?The big bang theory is a scientific theory that tries to explain the existence of the universe from the earliest known periods through small to large evolution.
In the first moments after the Big Bang, the universe was extremely hot and dense, and matter was formed as the universe cooled.
The formation of the matter is as a result of the following forces;
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You are driving your small, fuel-efficient car when you have a head-on collision with a big, fuel-efficient truck that is three times as massive as your car. Head-on means, for example that if you are traveling in the positive x direction, the truck is traveling in the negative x direction. Right before the collision, you were traveling at a speed of 3.0 m/s and right after the collision, both vehicles are at rest. Due to the conservation of the momentum, you can find the speed of the truck before the collision. What was the kinetic energy of the truck Ktruck before the collision when the kinetic energy of the car was Kcar
Explanation:
Momentum before = momentum after
mv + MV = 0
(m) (3.0 m/s) + (3m) (V) = 0
V = -1.0 m/s
The truck was moving at 1.0 m/s before the collision.
The kinetic energy of the car was:
KE = 1/2 m v²
Kcar = 1/2 m (3.0)²
Kcar = 9/2 m
Ktruck = 1/2 M V²
Ktruck = 1/2 (3m) (1.0)²
Ktruck = 3/2 m
Ktruck = 1/3 Kcar
So the truck had 1/3 the kinetic energy of the car.
By what mechanism is a person injured when he or she falls from a significant height? Select one: a. Kinetic energy is converted to potential energy; the potential energy is then converted into the work of bringing the body to a stop. b. As the person falls, the amount of kinetic energy is converted into work; work is then converted to kinetic energy upon impact. c. Potential energy is created as the person is falling; the potential energy is then converted into kinetic energy upon impact. d. Potential energy is converted to kinetic energy; the kinetic energy is then converted into the work of bringing the body to a stop.
Answer:
d. Potential energy is converted to kinetic energy; the kinetic energy is then converted into the work of bringing the body to a stop
Explanation:
- When the person starts his/her fall from a certain height h, he/she possesses gravitational potential energy:
[tex]U=mgh[/tex]
where m is the mass of the person, g is the acceleration due to gravity, h is the height.
- During the fall, the height h decreases, while the speed of the person increases, so gravitational potential energy is converted into kinetic energy:
[tex]K=\frac{1}{2}mv^2[/tex]
where
m is the mass of the person
v is the speed
- Just a moment before hitting the ground, h=0, so all the potential energy has been converted into kinetic energy
- When the person hits the ground, he/she comes a stop: this means that now the speed is zero (v=0), so the kinetic energy is zero as well. This occurs because all the kinetic energy has been converted into the work of bringing the body to a stop. (the work has been done by the ground on the person)
Crime scene investigators find that a car hit the ground 60m from the point where it left the cliff. The cliff is 45 m high. Approximately what speed was the car going when it left the cliff (assume no air resistance)?
Answer:
20 m/s
Explanation:
In the y direction:
y = y₀ + v₀ᵧ t + ½ gt²
0 m = 45 m + (0 m/s) t + ½ (-9.8 m/s²) t²
t = 3.03 s
In the x direction:
x = x₀ + v₀ₓ t + ½ at²
60 m = 0 m + v (3.03 s) + ½ (0 m/s²) (3.03 s)²
v = 19.8 m/s
Rounded to one sig-fig, the car's velocity was approximately 20 m/s.
A sample of gas initially has a volume of 859 ml at 565 k and 2.20 atm. What pressure will the sample have if the volume changes to 268 ml while the temperature is increased to 815 k?
Answer:
10.2 atm
Explanation:
Use ideal gas law:
PV = nRT
Initial number of moles is:
(2.20 atm) (0.859 L) = n (0.0821 atm L / mol / K) (565 K)
n = 0.0407 mol
At the new volume and temperature, the pressure is:
P (0.268 L) = (0.0407 mol) (0.0821 atm L / mol / K) (815 K)
P = 10.2 atm
We have that the pressure the sample have if the volume changes to 268 ml while the temperature is increased to 815 k is
[tex]P_2=10atm[/tex]
From the question we are told
A sample of gas initially has a volume of 859 ml at 565 k and 2.20 atm. What pressure will the sample have if the volume changes to 268 ml while the temperature is increased to 815 k
Generally the equation for the ideal gas is mathematically given as
PV=nRT
Where
[tex]\frac{P1V1}{T1}=\frac{P2V2}{T2}[/tex]
Therefore
[tex]P_2=\frac{P1V1T2}{V2T1}\\\\P_2=\frac{2.20*859*815}{268*565}[/tex]
[tex]P_2=10atm[/tex]
THEREFORE
the pressure the sample have if the volume changes to 268 ml while the temperature is increased to 815 k is
[tex]P_2=10atm[/tex]
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The photoelectric effect tells us that __________.
Find the angular speed of the minute hand and the hour hand of the famous clock in london
All clocks that keep the correct time have hands that move at the same speeds. I only have to decide whether the famous clock in London keeps the correct time. I'm thinking that if it didn't, it wouldn't have gotten to be so famous, or else the people of London would have fixed it by now. So I'm going to assume that it keeps the correct time.
Since the famous clock in London keeps the correct time, its minute hand makes one complete revolution around the clock's face every hour, and its hour hand makes one complete revolution every 12 hours.
When we're talking angular speeds, we usually talk in radians. One complete revolution is an angle of 2π radians.
Minute hand speed: 2π radian/hour
Speed = (2π/hr) x (1 hr/3600 sec)
Speed = 2π/3600 sec
Speed = 1.75 x 10⁻³ radian/sec
Speed = 0.1 degree/sec
Hour hand speed = 2π / 12 hours = π/6 radian per hour
Speed = (π / 6 hour) x (1 hour / 3600 sec)
Speed = 1.45 x 10⁻⁴ radian/sec
Speed = 30 degrees/hour
Speed = 8.3 x 10⁻³ degree/second
The angular speed of the minute hand of a clock is 2π rad/hour, and for the hour hand, it’s 2π rad/12 hours. This calculation comes from dividing the total rotation angle (2π rad) by the time it takes to complete that rotation. This utilizes the principles of rotational motion in Physics.
Explanation:To find the angular speed of the minute and hour hand on a clock, a concept from Physics, specifically rotational motion, is applied. The angular speed is defined as the change in angle per unit time. In a clock, a complete rotation, which is equal to 360° or 2π radians, takes an hour for the minute hand and 12 hours for the hour hand.
For the minute hand: it completes one rotation (360° or 2π radians) in 60 minutes (1 hour). So, its angular speed ω is equal to the total angle θ divided by the total time t: ω (minute) = θ / t = 2π / 1 hour.
For the hour hand: it completes one rotation in 12 hours. Hence, its angular speed is: ω (hour) = θ / t = 2π / 12 hours.
Please note that this calculation considers a simple ideal case. In real life scenarios, factors such as mechanism quality, temperature, even relativistic effects if the clock moves very fast, like the satellite clocks, can cause slight differences.
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When Anna eats an apple, the sugars in that apple are broken down into the substance called glucose. Glucose is then burned in her body for energy. One of the body parts that needs this energy is the heart, which beats due to electrical impulses. A byproduct of this glucose breakdown is the heat that warms her body and is later released. Which identifies the energy transformations that take place in Anna’s body as this process takes place? Mechanical energy is converted to kinetic energy, which is then converted to potential energy. Chemical energy is converted to thermal energy and electrical energy. Electrical energy is converted to chemical energy and thermal energy. Mechanical energy is converted to potential energy which is then converted to kinetic energy.
Answer:
Chemical energy is converted to thermal energy and electrical energy.
Explanation:
The sugar present in the apple is broken down into Glucose. This is chemical energy stored in the apple which is broken down into energy which is utilized by body for everyday works. The chemical energy gets converted to thermal energy which warms the body and electrical energy due to which the heart beats.
Answer:
Chemical energy is converted to thermal energy and electrical energy.
Explanation:
Plants get the energy they need for photosynthesis by absorbing
Plants absorb sunlight to fuel the process of photosynthesis, converting this light energy into chemical energy to produce glucose from carbon dioxide and water.
Explanation:Plants get the energy they need for photosynthesis by absorbing sunlight. This light is captured primarily through their leaves, specifically, the chlorophyll in the chloroplasts, which converts light energy into chemical energy, a procedure known as light-dependent reactions.
This energy is then used to generate glucose from carbon dioxide and water in a process commonly referred to as the 'light-independent reactions', or the Calvin cycle.
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A student pushes a 35-kg block on a frictionless, horizontal surface with a force of 18 N. What is the acceleration of the block ?
A. 1.0m/sSquared
B. 1.4m/sSquared
C. 1.6m/sSquared
D. 1.9m/sSquared
Newton wrote . . . F = m a
From that, we can derive . . . a = F/m
a = (18 N) / (35 kg)
a = 0.514... m/s^2
None of the choices says this.
Choice-D is the reciprocal of the correct answer ... the result of doing the division backwards ... m/F .
Leap years _____. happen because the Earth revolves around the sun in less than 365 days make up for the extra one-fourth day the Earth needs to orbit the sun add an extra day to the end of December, making the month 32 days long subtract a day from February, making the month only 27 days long
The Earth takes (365 and 1/4) days to orbit the sun. That's the length of our 'year'.
Since it's not really possible to make our calendar a quarter of a day longer every year, we make the calendar a whole day longer every 4 years.
So "Leap years" make up for the extra one-fourth day the Earth takes to orbit the sun.
The definition of parallel lines requires the undefined terms line and plane
Answer:
True
Explanation:
Answer:
Parallel lines never intersect, but they must be in the same plane. The definition does not require the undefined term point, but it does require plane. Because they intersect, perpendicular lines must be coplanar; consequently, plane is not required in the definition.
What did you include in your response? Check all that apply.
Parallel lines do not intersect.
Parallel lines must be coplanar.
Perpendicular lines intersect at one point.
Perpendicular lines intersect so plane is not required in the definition.
A friend asks you how much pressure is in your car tires. You know that the tire manufacturer recommends 30 psi, but it's been a while since you've checked. You can't find a tire gauge in the car, but you do find the owner's manual and a ruler. Fortunately, you've just finished taking physics, so you tell your friend, "I don't know, but I can figure it out." From the owner's manual you find that the car's mass is 1550 kg. It seems reasonable to assume that each tire supports one-fourth of the weight. With the ruler you find that the tires are 16 cm wide and the flattened segment of the tire in contact with the road is 14 cm long. What answer will you give your friend?
Answer:
25 psi
Explanation:
The weight of the car is:
W = mg
W = 1550 kg * 9.8 m/s²
W = 15,190 N
Divided by 4 tires, each tire supports:
F = W/4
F = 15,190 N / 4
F = 3797.5 N
Pressure is force divided by area, so:
P = F / A
P = (3797.5 N) / (0.16 m × 0.14 m)
P ≈ 170,000 Pa
101,325 Pa is the same as 14.7 psi, so:
P ≈ 170,000 Pa × (14.7 psi / 101,325 Pa)
P ≈ 25 psi
The pressure in each tire is ≈ 25 psi which falls within the recommended manufacturer pressure
Given data ;
mass of car ( m ) = 1550 kg
width of tires ( w ) = 16 cm = 0.16 m
length of tires ( l ) = 14 cm = 0.14 m
First step : Determine the Total weight of car
W = m*g ---- ( 1 )
= 1550 * 9.8 = 15,190 N
∴ Weight supported by each tire = ( W / 4 )
= 15,190 / 4 = 3797.5 N
Final step : determine the Pressure in the tires
P = F / A -------- ( 2 )
F ( force ) = 3797.5 N
A ( area ) = 0.14 * 0.16 = 0.0224
back to equation ( 2 )
P = 3797.5 / 0.0224
≈ 170,000 Pa
∴ Pressure in each tire ≈ 25 psi
Hence we can conclude that the pressure in each tire is ≈ 25 psi.
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How many calories are required to raise the temperature of 105 g of water from 30.0°c to 70.0°c?
Let's start by explaining that 1 Calorie ([tex]1 cal[/tex]) is defined as a unit of thermal energy that is equivalent to the amount of heat ([tex]Q[/tex]) needed to raise the temperature of 1 gram [tex]1g[/tex] of water by 1 degree Celsius [tex]1\°C[/tex].
The formula to calculate it is:
[tex]Q=m. c. \Delta T[/tex] (1)
Where:
[tex]m[/tex] is the mass
[tex]c[/tex] is the specific heat of the element. In the case of water [tex]c=1cal/g[/tex]
[tex]\Delta T[/tex] is the variation in temperature, which in this case is [tex]\Delta T=70\°C-30\°C=40\°C[/tex]
Rewriting equation (1) with the known values:
[tex]Q=(105g)(1 cal/g)(40\°C)[/tex]
[tex]Q=4200 cal[/tex]
A sound source A and a reflecting surface B move directly toward each other. Relative to the air, the speed of source A is 28.7 m/s, the speed of surface B is 62.2 m/s, and the speed of sound is 334 m/s. The source emits waves at frequency 1110 Hz as measured in the source frame. In the reflector frame, what are (a) the frequency and (b) the wavelength of the arriving sound waves? In the source frame, what are (c) the frequency and (d) the wavelength of the sound waves reflected back to the source?
(a) 1440.5 Hz
The general formula for the Doppler effect is
[tex]f'=(\frac{v+v_r}{v+v_s})f[/tex]
where
f is the original frequency
f is the apparent frequency
[tex]v[/tex] is the velocity of the wave
[tex]v_r[/tex] is the velocity of the receiver (positive if the receiver is moving towards the source, negative otherwise)
[tex]v_s[/tex] is the velocity of the source (positive if the source is moving away from the receiver, negative otherwise)
Here we have
f = 1110 Hz
v = 334 m/s
In the reflector frame (= on surface B), we have also
[tex]v_s = v_A = -28.7 m/s[/tex] (surface A is the source, which is moving towards the receiver)
[tex]v_r = +62.2 m/s[/tex] (surface B is the receiver, which is moving towards the source)
So, the frequency observed in the reflector frame is
[tex]f'=(\frac{334 m/s+62.2 m/s}{334 m/s-28.7 m/s})1110 Hz=1440.5 Hz[/tex]
(b) 0.232 m
The wavelength of a wave is given by
[tex]\lambda=\frac{v}{f}[/tex]
where
v is the speed of the wave
f is the frequency
In the reflector frame,
f = 1440.5 Hz
So the wavelength is
[tex]\lambda=\frac{334 m/s}{1440.5 Hz}=0.232 m[/tex]
(c) 1481.2 Hz
Again, we can use the same formula
[tex]f'=(\frac{v+v_r}{v+v_s})f[/tex]
In the source frame (= on surface A), we have
[tex]v_s = v_B = -62.2 m/s[/tex] (surface B is now the source, since it reflects the wave, and it is moving towards the receiver)
[tex]v_r = +28.7 m/s[/tex] (surface A is now the receiver, which is moving towards the source)
So, the frequency observed in the source frame is
[tex]f'=(\frac{334 m/s+28.7 m/s}{334 m/s-62.2 m/s})1110 Hz=1481.2 Hz[/tex]
(d) 0.225 m
The wavelength of the wave is given by
[tex]\lambda=\frac{v}{f}[/tex]
where in this case we have
v = 334 m/s
f = 1481.2 Hz is the apparent in the source frame
So the wavelength is
[tex]\lambda=\frac{334 m/s}{1481.2 Hz}=0.225 m[/tex]
How many category 5 hurricanes since 2000
Answer:
Explanation:
“Officially, the decade with the most Category 5 hurricanes is 2000–2009, with eight Category 5 hurricanes having occurred: Isabel (2003), Ivan (2004), Emily (2005), Katrina (2005), Rita (2005), Wilma (2005), Dean (2007), and Felix (2007).”
A 2.0-kg ball moving eastward at 3.0 m/s suddenly collides with and sticks to a 4.0-kg ball moving northward at 2.0 m/s. What is the magnitude of the momentum of this system just after the collision?
Answer:
10 kg m/s
Explanation:
Due to the law of conservation of momentum, the total momentum after the collision must be equal to the total momentum before the collision.
The momentum of each ball is given by:
p = mv
where m is the mass of the ball and v its velocity.
The momentum of ball 1 is:
p = mv = (2.0 kg)(3.0 m/s) = 6.0 kg m/s in the eastward direction
The momentum of ball 2 is:
p = mv = (4.0 kg)(2.0 m/s) = 8.0 kg m/s in the northward direction
The two momenta are in perpendicular directions, so the magnitude of the total momentum can be found as:
[tex]p=\sqrt{p_1^2 + p_2^2 }= \sqrt{(6.0 kg m/s)^2 + (8.0 kg m/s)^2}=10 kg m/s[/tex]
and due to the law of conservation of the momentum, this is also equal to the total momentum after the collision.
The magnitude of the momentum of this system just after the collision is about 10.0 kg.m/s
[tex]\texttt{ }[/tex]
Further explanationLet's recall Impulse formula as follows:
[tex]\boxed {I = \Sigma F \times t}[/tex]
where:
I = impulse on the object ( kg m/s )
∑F = net force acting on object ( kg m /s² = Newton )
t = elapsed time ( s )
Let us now tackle the problem!
[tex]\texttt{ }[/tex]
Given:
mass of first ball = m₁ = 2.0 kg
velocity of first ball = v₁ = 3.0i m/s
mass of second ball = m₂ = 4.0 kg
velocity of second ball = v₂ = 2.0j m/s
Asked:
magnitude of the final momentum = p = ?
Solution:
We will use Conservation of Momentum formula to solve this problem:
[tex]\texttt{Total Momentum Before Collision = Total Momentum After Collision}[/tex]
[tex]m_1 v_1 + m_2 v_2 = \overrightarrow{p}[/tex]
[tex]2.0 ( 3.0\ \widehat{i} ) + 4.0 ( 2.0 \ \widehat{j} ) = \overrightarrow{p}[/tex]
[tex]\overrightarrow{p} = 6.0 \ \widehat{i} + 8.0 \ \widehat{j}[/tex]
[tex]|\overrightarrow{p}| = \sqrt{ 6.0^2 + 8.0^2 }[/tex]
[tex]|\overrightarrow{p}| = 10.0 \texttt{ kg.m/s}[/tex]
[tex]\texttt{ }[/tex]
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Answer detailsGrade: High School
Subject: Physics
Chapter: Dynamics
Why are metals generally good conductors of electricity?
Answer:
Let's start by explaining that a material is a good electrical conductor when it allows the flow of electric current without much resistance.
This is achieved because the atoms of which the material is composed have electrons in their valence shell, which is the outermost layer where the electrons (the particles responsible for transporting electricity) can be easily detached to form atomic bonds, so there is no need of a huge amount of energy for these electrons to jump from one atom to another and form stable chemical bonds.
This is what happens with metals, because they have an atomic structure so united and stable that when an electric flow passes through it, the electrons in the metal flow unimpeded.
Metals are good conductors because the molecules that are inside the metal are tightly packed together. This is why the heat moves through the metal quickly.
The binding energy of a nucleus can be found using
Answer:
converting that mass to energy by using E=mc2. Mass must be in units of kg. Once this energy, which is a quantity of joules for one nucleus, is known, it can be scaled into per-nucleon and per-mole quantities.
Explanation:
Answer:
An elephants balls
Explanation:
A horizontal spring has one end firmly attached to a wall and the other end attached to a mass. The mass can slide freely on a smooth, horizontal surface with no friction. The mass is pulled away from the equilibrium position by a distance A in the positive x-direction and then released so that it oscillates in simple harmonic motion with frequency f. What will happen to the frequency of the oscillation if the mass is doubled?
Explanation:
The frequency of a spring is:
f = 1/(2pi) sqrt(k / m)
If m doubles, then f decreases by a factor of 1/sqrt(2).
Doubling the mass attached to a spring in a frictionless simple harmonic oscillator will decrease the frequency of oscillation by a factor of √2, or approximately 0.7071 times the original frequency.
Explanation:In a simple harmonic oscillator like the mass-spring system described, the frequency of oscillation is given by f = (1/2π) * √(k/m), where k represents the spring constant and m the mass attached to the spring. If the mass is doubled, the frequency of the oscillation will decrease because the frequency is inversely proportional to the square root of the mass. Therefore, if the mass increases by a factor of two, the new frequency will be f' = (1/2π) * √(k/2m), which is f' = f/√2. This implies that the frequency will decrease by a factor of √2, or approximately 0.7071 times the original frequency.
Check all that apply. The magnetic force on the current-carrying wire is strongest when the current is parallel to the magnetic field lines. The direction of the magnetic force acting on a current-carrying wire in a uniform magnetic field is perpendicular to the direction of the field. The direction of the magnetic force acting on a current-carrying wire in a uniform magnetic field is perpendicular to the direction of the current. The magnetic force on the current-carrying wire is strongest when the current is perpendicular to the magnetic field lines.
Answer:
The direction of the magnetic force acting on a current-carrying wire in a uniform magnetic field is perpendicular to the direction of the field.
The direction of the magnetic force acting on a current-carrying wire in a uniform magnetic field is perpendicular to the direction of the current.
The magnetic force on the current-carrying wire is strongest when the current is perpendicular to the magnetic field lines.
Explanation:
The magnitude of the magnetic force exerted on a current-carrying wire due to a magnetic field is given by
[tex]F=ILB sin \theta[/tex] (1)
where I is the current, L the length of the wire, B the strength of the magnetic field, [tex]\theta[/tex] the angle between the direction of the field and the direction of the current.
Also, B, I and F in the formula are all perpendicular to each other. (2)
According to eq.(1), we see that the statement:
"The magnetic force on the current-carrying wire is strongest when the current is perpendicular to the magnetic field lines."
is correct, because when the current is perpendicular to the magnetic field, [tex]\theta=90^{\circ}, sin \theta = 1[/tex] and the force is maximum.
Moreover, according to (2), we also see that the statements
"The direction of the magnetic force acting on a current-carrying wire in a uniform magnetic field is perpendicular to the direction of the field. "
"The direction of the magnetic force acting on a current-carrying wire in a uniform magnetic field is perpendicular to the direction of the current. "
because F (the force) is perpendicular to both the magnetic field and the current.
The magnetic force on a current-carrying wire in a uniform magnetic field is perpendicular to both the magnetic field lines and the direction of the current. The force is strongest when the current is perpendicular to the magnetic field lines, and is zero when the current runs parallel to the magnetic field lines.
Explanation:According to the principles of magnetism and the right-hand rule, the magnetic force acting on a current-carrying wire in a uniform magnetic field is perpendicular to both the magnetic field and to the current direction. The strength of the magnetic force on the wire is dictated by the equation F = I x B, where F is the force, I represents the current, and B is the strength of the magnetic field.
When the current flows parallel to the magnetic field lines, the force experienced by the wire is actually zero due to the nature of the cross product in the force formula. However, the magnetic force on the current-carrying wire is strongest when the current is perpendicular to the magnetic field lines. This is because the effect of the magnetic force is most significant when these two quantities are at right angles to each other.
In terms of the direction of the force, you can use the right-hand rule. If you point your thumb in the direction of the current, and your fingers in the direction of the magnetic field, your palm will point in the direction of the force on the wire.
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A car is traveling at an initial velocity of 25 m/s slows to a stop in 10 seconds. What is the acceleration of the car?
Answer:
2.5 m/s^2
Explanation:
the formula for acceleration (or the one you use in this case) is a=vf-vi/t
where vf is equal to final velocity, vi is equal to initial velocity, and t is equal to time.
vf= 25 m/s
vi= 0m/s
t=10s 25-0=25, 25/10=2.5 therefore it is 2.5m/s^2
During a phase change, the temperature of a substance _____.
A)decreases
B)increases
C)stays the same
During a phase change, the temperature of a substance (c). stays the same.
The temperature remains same during the phase change.
Answer: Option C
Explanation:
The term “change of phase” is similar to “change of state”. When there is a change of substance from a state to the other state or phase, it is known as changes in its state. This change of state occurs due to the change of heat.
When a substance changes the phase, either the heat comes out or goes in the substance. Although there occur a change in the content of heat present in the substance, the temperature will not change. It remains constant. When ice melts it becomes water and the water vaporizes which becomes water vapour.
The small currents in axons corresponding to nerve impulses produce measurable magnetic fields. a typical axon carries a peak current of 0.040 μa. what is the strength of the field at a distance of 1.2 mm
Answer:
[tex]6.66\cdot 10^{-12}T[/tex]
Explanation:
The magnetic field produced by a current-carrying wire is given by
[tex]B=\frac{\mu_0 I}{2\pi r}[/tex]
where
[tex]\mu_0[/tex] is the vacuum permeability
I is the current
r is the distance from the wire
In this problem we have
[tex]I=0.040 \mu A=4\cdot 10^{-8}A[/tex]
r = 1.2 mm = 0.0012 m
So the magnetic field strength is
[tex]B=\frac{(4\pi \cdot 10^{-7} H/m)(4\cdot 10^{-8}A)}{2\pi (0.0012 m)}=6.66\cdot 10^{-12}T[/tex]
An object of mass m is dropped from height h above a planet of mass M and radius R. Find an expression for the object's speed as it hits the ground. Express your answer in terms of the variables m, M, h, R and appropriate constants.
Answer:
v = √(2 MGh) / R
Explanation:
Assuming that h is much smaller than R, we can say the acceleration of gravity is approximately constant during the fall.
Potential energy = Kinetic energy
mgh = 1/2 mv²
v = √(2gh)
v = √(2 (MG/R²) h)
v = √(2 MGh) / R