Question: If the kinetic energy of a ball is doubled, what happens to the momentum of the ball?
Answer: 1.41 times larger
Question: A 4.0 kg ball is traveling at 5.0 m/s and strikes a wall. The 4.0 kg ball bounces off the wall with a velocity of 4.0 m/s. What is the change in momentum of the ball?
Answer: 36 kg m/s
Question: Alex throws a 0.15-kg rubber ball down onto the floor. The ball’s speed just before impact is 6.5 m/s, and just after is 3.5 m/s. If the ball is in contact with the floor for 0.025 s, what is the magnitude of the average force applied by the floor on the ball?
Answer: 60 N
Question: A 4.0 kg ball is moving at 3.0 m/s to the NORTH and a 5.0 kg ball is moving at 2.0 m/s to the NORTHWEST. What is the total momentum of the system?
Answer: 20.3 kg m/s at an angle of 69.7 degrees NORTH of WEST
Question: During a snowball fight two balls with masses of 0.4 and 0.6 kg, respectively, are thrown in such a manner that they meet head-on and combine to form a single mass. The magnitude of initial velocity for each is 15 m/s. What is the speed of the 1.0-kg mass immediately after collision?
Answer: 3 m/s
Question: A 2 500-kg truck moving at 10.00 m/s strikes a car waiting at a traffic light, hooking bumpers. The two continue to move together at 7.00 m/s. What was the mass of the struck car?
Answer: 1 070 kg
Question: A railroad freight car, mass 20 000 kg, is allowed to coast along a level track at a speed of 2.0 m/s. It collides and couples with a 50 000-kg loaded second car, initially at rest and with brakes released. What percentage of the initial kinetic energy of the 20 000-kg car is preserved in the two-coupled cars after collision?
Answer: 71%
Question: A 7.0-kg bowling ball strikes a 2.0-kg pin. The pin flies forward with a velocity of 6.0 m/s; the ball continues forward at 4.0 m/s. What was the original velocity of the ball?
Answer: 5.7 m/s
Question: Two billiard balls have velocities of 2.0 m/s and –1.0 m/s when they meet in an elastic head-on collision. What is the final velocity of the first ball after collision?
Answer: –1.0 m/s
Question: A 75-kg swimmer dives horizontally off a 500-kg raft. If the diver’s speed immediately after leaving the raft is 4 m/s, what is the corresponding raft speed?
Answer: 0.6 m/s