Which example identifies a change in motion that produces acceleration?
a. a ball moving at a constant speed around a circular track
b. a particle moving in a vacuum at constant velocity
c. a speed skater moving at a constant speed on a straight track
d. a vehicle moving down the street at a steady speed?

Answer:

Time period

Explanation:

The time taken by a wave to complete one cycle is called the time period of a wave. It is denoted by T. The number of vibration per second is called the frequency of the wave.

The relation between the time period and the frequency is inverse i.e.

[tex]T=\dfrac{1}{\nu}[/tex]

If the number of vibrations increases its time period will decrease.

Similarly, for a simple pendulum the time period to complete one cycle is :

[tex]T=2\pi\sqrt{\dfrac{l}{g}}[/tex]

l and g are length of pendulum and acceleration due to gravity.

The angular speed of the minute hand of a watch is calculated by dividing the total angle of rotation (2π rad) by the period of rotation (3600 s), which equals 0.1047 rad/min. This indicates the degree of the minute hand's rotation per minute. The right-hand rule also designates the angular velocity's direction.

The angular speed of the minute hand of a watch refers to the degree of rotation of the minute hand per unit of time. In the particular case of a watch, the minute hand completes one full revolution (360° or 2π rad) in one hour (60 minutes or 3600 seconds). Therefore, the angular speed ω can be calculated as the total angle of rotation (2π rad) divided by the period of rotation, which is 3600 seconds.

Thus, the angular speed is calculated as ω = 2π rad/3600 s. By converting this to radian per minute, which is a more typical unit for a watch, we obtain that the angular speed of the minute hand of a watch is 0.1047 rad/min. This means that in each minute, the minute hand rotates 0.1047 radians.

This concept and calculation is part of what's studied in rotational motion in physics, where the right-hand rule can also be used to determine the direction of the angular velocity vector.

https://brainly.com/question/32114693

#SPJ12

The average velocity can be calculated using the formula:

v = d / t

For the 1st car, the velocity is calculated as:

v1 = 8.60 m / 1.80 s = 4.78 m / s

While that of the 2nd car is:

v2 = 8.60 m / 1.66 s = 5.18 m / s

Now we can solve for the acceleration using the formula:

v2^2 = v1^2 + 2 a d

Rewriting in terms of a:

a = (v2^2 – v1^2) / 2 d

a = (5.18^2 – 4.78^2) / (2 * 8.6)

a = 0.23 m/s

Therefore the train has a constant acceleration of about 0.23 meters per second.

Answer:

its b on oddessey ware

Explanation:

Final answer:

During the electrolysis of molten potassium bromide, the half-reaction that occurs at the cathode is the reduction of potassium ions (K+) to form potassium metal (K).

Explanation:

The half-reaction that occurs at the cathode during the electrolysis of molten potassium bromide is the reduction of potassium ions (K+) to form potassium metal (K).

The half-reaction can be represented as:

2K+ + 2e- -> 2K

At the cathode, positive ions are reduced and gain electrons to form neutral atoms or molecules.

The work done when lifting a 185 g tomato by 17.9 m is approximately 32.5 joules, calculated using the weight of the tomato as the force and the distance it is lifted.

To calculate the work done when lifting an object, we can use the formula Work (W) = Force (F) × Distance (D) × cos(θ), where θ is the angle between the force and the displacement. In the case of lifting an object vertically, the angle is 0°, so the cosine term is 1, and the equation simplifies to W = F × D. For a 185 g tomato lifted 17.9 m, we first need to convert the mass of the tomato to kilograms by dividing by 1000, which gives us 0.185 kg. The force is equal to the weight of the tomato, which is the mass (m) multiplied by the acceleration due to gravity (g = 9.8 m/s²), F = m × g. Thus, the force is F = 0.185 kg × 9.8 m/s² = 1.813 N. The work done is then W = 1.813 N × 17.9 m = 32.463 J, which we round to 32.5 J when expressing it with three significant figures.

Answer:

B. Certified

Explanation: I agree with the other person and i also believe it is correct

The density of the concrete is approximately 0.965 g/cm³. The result does not support the statement that rebar is mostly iron.

The density of a substance can be calculated by dividing its mass by its volume. In this case, the mass of the concrete is 43.8 grams and the volume is calculated by multiplying the length, width, and height, which is 3.7 cm x 2.1 cm x 5.8 cm = 45.4014 cm³ (rounded to the nearest 0.0001 cm³). Therefore, the density of the concrete is 43.8 g / 45.4014 cm³ ≈ 0.965 g/cm³.

(b) Since the density of the concrete in (a) is less than the density of iron (approximately 7.87 g/cm³), the result does not support the statement that rebar is mostly iron.

Final answer:

You lurch forward in a bus that suddenly slows due to Newton's First Law of Motion, or the law of inertia, which suggests an object in motion stays in motion unless acted on by an unbalanced force. When the bus accelerates, inertia causes you to feel pushed back as your body prefers to remain at rest. Understanding this law helps in recognizing the importance of safety measures like seatbelts.

Explanation:

Understanding Movement in a Bus: Newton's First Law of Motion

When a bus suddenly slows down, you lurch forward because of Newton's First Law of Motion, also known as the law of inertia. This law states that an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force. Since your body wants to keep moving at the same speed the bus was going before it slowed down, you lurch forward when the bus decelerates.

Similarly, when the bus speeds up, you might feel like you are being pushed back into your seat. This is again due to the law of inertia. Your body wants to remain at its state of rest (or moving at a constant speed if the bus was already moving), so when the bus accelerates, it creates a temporary imbalance, making you feel pushed back.

Using seatbelts or holding onto something stable inside the bus can counteract these effects by providing the necessary force to keep you in place, thereby preventing injury and ensuring safety.

Why Understanding Newton's First Law is Important

The applications of Newton's First Law are seen in everyday life, not just in theoretical physics. It explains a wide range of phenomena, from why it's crucial to wear a seatbelt to the importance of headrests in preventing whiplash injuries. Understanding these principles can help improve personal safety and awareness in moving vehicles.

Answer:

0.50 s

Explanation:

you're welcome

Answer:

The third answer is correct:)

Explanation:

<<<<<<<<<< B is the answer >>>>>>>

Answer:

Applied force, weight, normal force and frictional force

Explanation:

Bob is pushing a lawn mower up a hill with the mower tilting slightly to the right. We have to write the forces acting on the mower.

The following are the forces that are acting on the mower.

1. Applied force - The force with which Bob is pushing a lawn.

2. Weight - Its weight is equal to, W = m g

3. Normal force - that balances its weight

4. Frictional force - It always opposes the motion of the mower.

Hence, this is the required solution.

The lawn mower is acted upon by four different forces.

Vector quantities are those quantities that posses both magnitude and direction. Force is a vector quantity. Hence, the resultant force acting on a lawn mover can be obtained as the resultant of the four forces that act on the mower.

The four forces that act on the lawn mower are;

Hence, the lawn mower is acted upon by four different forces.

Learn more about forces: https://brainly.com/question/26115859

Answer:

In a collision, the SECOND collision is when an unsecured driver strikes the inside of the vehicle.

Explanation:

When driver in the car is unsecured then it means that the driver is not having his safety seat belt.

Now when collision occurs between the car and some other object then due to the property of inertia of driver it has tendency to move in the direction of his motion.

So the driver will continue his motion and collide with other parts of the car and due to this he may got injured.

So in any car collision there are two types of collision

first is the collision of car with other objects

second collision is between car and the driver inside the car

Answer:

A. 468 Hz while approaching, 440 Hz through the crossing, 415 Hz while receding

Explanation:

When bus is approaching the stand where boy is standing then the frequency is given as

now we know that

[tex]f_0 = 440 Hz[/tex]

[tex]v = 330 m/s[/tex]

[tex]v_b = 20 m/s[/tex]

frequency is given by

[tex]f_1 = f_0 \frac{v}{v - v_b}[/tex]

now plug in the data in the equation

[tex]f_1 = 440 \times \frac{330}{330 - 20}[/tex]

[tex]f_1 = 468 Hz[/tex]

Now when bus is moving away from the bus stop then frequency is given as

[tex]f_2 = f_0 \frac{v}{v + v_b}[/tex]

[tex]f_2 = 440 \times \frac{330}{330 + 20}[/tex]

[tex]f_2 = 415 Hz[/tex]

so here correct answer would be

A. 468 Hz while approaching, 440 Hz through the crossing, 415 Hz while receding