A student throws a 1.8kg ball horizontally off the top of a building with an initial speed 3.85 m/s. At the same time, another student throws a ball with equal mass along the same trajectory with an initial speed of 2.75 m/s. Which of the balls hits the ground first?

Alice has a mass of 62.0 kg and Bob has a mass of 84.0 kg and they are initially standing at rest with respect to one another on a frictionless surface. They push against each other such that Alice moves at 0.04 m/s relative to her starting point. With what speed does Bob move away from his initial position? a. 0.03 m/s b. 0.09 m/s c. 1.21 m/s d. 32.2 m/s e. 1.6 m/s

A 4,400 kg barrel rests on a frozen pond. The barrel is loaded with a 36 kg ball. The barrel fires the ball horizontally. If the barrel retreats at a velocity of 1.8 m/s.  What is the velocity of the ball at the exit?     A. 180 m/s     B. 200 m/s     C. 220 m/s     D. 240 m/s     E. 260 m/s

2. A 'small' asteroid with a mass of 1000kg is moving through deep space with a constant velocity of 30 m/s. Suddenly the small asteroid collides with a large asteroid possessing a mass of 10,000kg. The large asteroid was initially at rest and the collision causes the small mass to become completely embedded within the larger one so that they are now one combined mass. a. What is the speed of the combined mass system after the collision? b. How many Joules of energy were lost due to the collision?

Holding a slingshot at arm's length, he pulls the light elastic band back to his chin and releases it to launch a stone horizontally with a speed of 200 cm/s. Using the same procedure, a bean is thrown with a speed of 600 cm/s. What is the ratio of the mass of the bean to the mass of the stone? a. 1/3 b. 3 c. 9 d. 1/9 e. 1

Kaya, a crew member on an interplanetary space ship, is on a spacewalk.  She realizes that her ship is moving away from her at 0.5 m/s. She and her spacesuit have a total mass of 95 kg. Her space suit includes a 15 kg backpack, which is included in the 95 kg total mass.a). What is the minimum velocity she will have to throw the backpack so that she can gain enough velocity to eventually catch up with the ship? b). Kaya applies an average force of 400 N to the backpack for 0.05 seconds. Will Kaya make it back to the ship? If so, determine how much time it will take for her to reach the ship. If not, determine how much more force she would need to apply to make it back.

Two skaters on in-line skates, Lisa and Bart, are initially at rest. They push apart and start moving in opposite directions. If Lisa’s speed just after they push apart is 2.0 m/s and her mass is 85% of Bart’s mass, how fast is Bart moving at that time? A. 4.7 m/s B. 1.7 m/s C. 3.7 m/s D. 2.7 m/s

A 4.00kg ball hits a wall moving at a speed of 9.0m/s at and angel of 45.0 degrees. If the wall does not move due to the collision at what speed and angle does the ball at the end of the interaction?

Two ice skaters push off against one another starting from a stationary position. The 45-kg skater acquires a speed of 0.375 m/s. What speed does the 60-kg skater acquire? a. 0.21 m/s b. 0.55 m/s c. 0.28 m/s d. 0.14 m/s

1. Write the scalar equation for the conservation of momentum in the x-direction where Vbx is the unkwown Solve this for Vbx. 2. Write a scalar equation for the conservation of momentum in the y-direction where Vby is the unknown. Solve this for Vby. 3. Determine the vector vb. Draw the puck's path on the diagram. 4. Determine the total kinetic energy before the collision. 5. Determine the total kinetic energy after the collision. 6. What type of collision was it? Explain.