11. Momentum & Impulse

How fast would you have to throw a 150-g rock for it to have the same momentum as a 10-g sniper rifle bullet traveling at 900 m/s?

Two vehicles are approaching an intersection. One is a 2500-kg pickup traveling at 14.0 m/s from east to west (the -x-direction), and the other is a 1500-kg sedan going from south to north (the +y-direction) at 23.0 m/s. What are the magnitude and direction of the net momentum?

Two vehicles are approaching an intersection. One is a 2500-kg pickup traveling at 14.0 m/s from east to west (the -x-direction), and the other is a 1500-kg sedan going from south to north (the +y-direction) at 23.0 m/s. Find the x- and y-components of the net momentum of this system.

What is the magnitude of the momentum of a 32-g sparrow flying with a speed of 8.4 m/s?

(II) Suppose the conveyor belt of Example 9–20 is retarded by a friction force of 150 N. Determine the required output power (hp) of the motor as a function of time from the moment gravel first starts falling (t = 0) until 3.0 s after the gravel begins to be dumped off the end of the 22-m-long conveyor belt.

(III) A sled filled with sand slides without friction down a 32° slope. Sand leaks out a hole in the sled at a rate of 2.0 kg/s. If the sled starts from rest with an initial total mass of 45.0 kg, how long does it take the sled to travel 120 m along the slope?

The force on a particle of mass m is given by $\vec{F}=26\vec{i}-12t^2\vec{j}$ where F is in N and t in s. What will be the change in the particle’s momentum between t = 1.0 s and t = 2.0 s?

What are the velocities of a 75 kg skydiver falling with $\overrightarrow{p}=-4100j\text{ kg m/s}$?

At what speed do a bicycle and its rider, with a combined mass of 100 kg, have the same momentum as a 1500 kg car traveling at 5.0 m/s?

FIGURE EX11.6 is an incomplete momentum bar chart for a collision that lasts 10 ms. What are the magnitude and direction of the average collision force exerted on the object?

A tennis player swings her 1000g racket with a speed of 10 m/s. She hits a 60g tennis ball that was approaching her at a speed of 20 m/s. The ball rebounds at 40 m/s. If the tennis ball and racket are in contact for 10 ms, what is the average force that the racket exerts on the ball? How does this compare to the gravitational force on the ball?

A particle of mass m is at rest at t = 0. Its momentum for t > 0 is given by p_x = 6t² kg m/s, where t is in s. Find an expression for F_x(t), the force exerted on the particle as a function of time.