Exam 7: Impulse and Momentum

A 0.015-kg marble moving to the right at 0.40 m/s has a head-on, elastic collision with a 0.045-kg marble sitting at rest on a smooth, level surface. Which of the following are the correct magnitudes and directions of the velocities of the two marbles after the collision? 0.015 kg marble 0.045 kg marble

Two objects of equal mass collide on a horizontal frictionless surface. Before the collision, object A is at rest while object B has a constant velocity of 12 m/s. After the collision, the two objects are stuck together. What is the speed of the composite body (A +B) after the collision?

A 4.0-kg block slides along a frictionless surface with a constant speed of 5.0 m/s as shown. Two seconds after it begins sliding, a horizontal, time-dependent force is applied to the mass. The force is removed eight seconds later. The graph shows how the force on the block varies with time. -What is the magnitude of the total impulse of the force acting on the block?

Car One is traveling due north and Car Two is traveling due east. After the collision shown, Car One rebounds in the due south direction. Which of the numbered arrows is the only one that can represent the final direction of Car Two?

Two asteroids are drifting in space with trajectories shown. Assuming the collision at point O between them is completely inelastic, at what angle from its original direction is the larger asteroid deflected?

A space vehicle of mass m has a speed v. At some instant, it separates into two pieces, each of mass 0.5m. One of the pieces is at rest just after the separation. -What is the kinetic energy of the moving piece just after the separation?

A 1000-kg car traveling east at 20 m/s collides with a 1500-kg car traveling west at 10 m/s. The cars stick together after the collision. What is the common velocity of the cars after the collision?

While a car is stopped at a traffic light in a storm, raindrops strike the roof of the car. The area of the roof is 5.0 m². Each raindrop has a mass of 3.7 × 10^-4 kg and speed of 2.5 m/s before impact and is at rest after the impact. If, on average at a given time, 150 raindrops strike each square meter, what is the impulse of the rain striking the car?

A mother is holding her 4.5-kg baby in her arms while riding in a car moving at 22 m/s. The car is involved in a head-on collision and stops within 1.5 seconds. What is the magnitude of the force exerted by the baby on his mother's arms?

The head of a hammer (m = 1.5 kg) moving at 4.5 m/s strikes a nail and bounces back with the same speed after an elastic collision lasting 0.075 s. What is the magnitude of the average force the hammer exerts on the nail?

A 0.050-kg lump of clay moving horizontally at 12 m/s strikes and sticks to a stationary 0.15-kg cart that can move on a frictionless air track. Determine the speed of the cart and clay after the collision.

A stationary 4-kg shell explodes into three pieces. Two of the fragments have a mass of 1 kg each and move along the paths shown with a speed of 10 m/s. The third fragment moves upward as shown. -What is the speed of the third fragment?

A 2.0-kg pistol fires a 1.0-g bullet with a muzzle speed of 1000 m/s. The bullet then strikes a 10-kg wooden block resting on a horizontal frictionless surface. The block and the embedded bullet then slide across the surface. -The explosive charge in the pistol acts for 0.001 s. What is the average force exerted on the bullet while it is being fired?

A 0.10-kg cart traveling in the positive x direction at 10.0 m/s collides with a 0.30-kg cart at rest. The collision is elastic. What is the velocity of the 0.10-kg cart after the collision?

A bullet of mass m is fired at speed v₀ into a wooden block of mass M. The bullet instantaneously comes to rest in the block. The block with the embedded bullet slides along a horizontal surface with a coefficient of kinetic friction $\mu$ . Which one of the following expressions determines how far the block slides before it comes to rest (the magnitude of displacement s in the figure)?

Jennifer is walking at 1.22 m/s. If Jennifer weighs 552 N, what is the magnitude of her momentum?

Which one of the following statements concerning momentum is true?

A stationary bomb explodes in space breaking into a number of small fragments. At the location of the explosion, the net force due to gravity is zero newtons. Which one of the following statements concerning this event is true?

A rocket is launched vertically from rest; and it burns fuel at a constant rate of 136 kg/s. Exhaust gases are expelled with a speed of 5.25 × 10³ m/s relative to the rocket. What is the magnitude of the thrust?

An object of mass 3m, initially at rest, explodes breaking into two fragments of mass m and 2m, respectively. Which one of the following statements concerning the fragments after the explosion is true?