Linear Momentum & Impulse (College Board AP® Physics 1: Algebra-Based): Exam Questions

A rubber ball and a clay ball of equal mass are released from the same height and strike the ground at the same speed. The rubber ball bounces off the ground, while the clay ball sticks to it.

Which ball delivers a larger impulse to the ground, and why?

An airsoft gun fires $0.40\mathrm{g}$ spherical pellets at a rate of 100 pellets per minute. The pellets leave the airsoft gun at a velocity of $45\mathrm{m}/\mathrm{s}$ and strike a fixed steel block. The pellets rebound off the block with the same velocity as they were fired.

Which of the following is most nearly the magnitude of the average force exerted on the steel block by the stream of pellets?

A ball of mass $m$ with speed $v$ strikes a wall at an angle $\theta$ to the normal, as shown in the diagram. It then rebounds with the same speed and at the same angle.

Which of the following expressions correctly represents the magnitude of the impulse delivered to the wall by the ball?

The graph shows the force acting on an object as a function of time. The object has a mass of $2\mathrm{kg}$ and a velocity of $-3.0\mathrm{m}/\mathrm{s}$ when $t=0$.

Which of the following is most nearly the velocity of the object at $t=5\mathrm{s}$?

A cart moves along a straight line while a varying net force is exerted on it in the direction of its motion. The graph shows the cart’s momentum $p$ as a function of time $t$. The five labeled points divide the graph into four sections.

Which of the following correctly ranks the magnitude of the average net force on the cart during the four sections of the graph?

A cannonball of mass $10\mathrm{kg}$ is fired at a speed of $24\mathrm{m}/\mathrm{s}$ and makes an angle of $60°$ with the horizontal. At the peak of its trajectory, the cannonball passes straight through a wall and loses $75\%$ of its kinetic energy.

What is the magnitude of the impulse exerted by the cannonball on the wall?

An object moves in the positive direction along a straight line. The graph shows the net force $F_{net}$ acting on the object as a function of displacement $x$. The object starts from rest at displacement $x=0$ and time $t=0$.

Which of the following graphs could represent the momentum$p$ of the object as a function of time $t$?

A wooden block of mass 150 g is supported on brackets at a height of 4.0 m above the ground, as shown in the figure. A bullet of mass 10 g is shot vertically upwards into the wooden block. When the bullet strikes the block, it passes straight through it and loses 90% of its initial kinetic energy. The magnitude of the impulse exerted by the bullet on the block is 1.4 kg m/s. After the collision, the bullet continues to rise to a height above the brackets.

Which of the following is most nearly the maximum height above the ground the bullet reaches?

A ball dropped from height $h$ rebounds to height $\frac{5}{8}h$. During the collision with the ground, the average force exerted on the ball is $F_1$. When the same ball is dropped from a greater height $H$, it rebounds to the same initial drop height $h$. This time, the average force exerted by the ground on the ball is $F_2$. In both collisions, the proportion of kinetic energy lost and the time the ball is in contact with the ground are the same.

What is the ratio of the average force exerted on the ball when dropped from the greater height to the average force exerted on the ball when dropped from the lower height, $\frac{F_2}{F_1}$?

A pitching machine positioned $1.0\mathrm{m}$ above the ground launches a baseball of mass $145\mathrm{g}$ horizontally at a speed of $35\mathrm{m}/\mathrm{s}$. The baseball player strikes the ball with their bat, making contact with it for $2.0\mathrm{ms}$. After the collision, the ball rebounds at an angle of $60°$ above the horizontal and reaches a maximum height of $24.5\mathrm{m}$ above the ground, as shown in the figure.

Which of the following is most nearly the magnitude of the average force exerted by the bat on the baseball in the horizontal direction?