Momentum
A 20 kg bowling ball is initially moving at 8 m/s to the right.
160 Kgm/s (no units, no points)
An object moving with 35kgm/s comes to a complete stop. The impulse is:
-35kgm/s
A 2kg mass is sliding at 5 m/s and collides with a 1kg block that is initially at rest. The speed they both move with after the collision is
3.33 m/s
A perfectly elastic collision is a collision in which the objects bounce apart and ......
100% Energy conserved
How does an air mattress protect a stunt person landing on the ground after a stunt?
Lengthens the time of contact/force applied
A 45kg cat is walking at 2 m/s
90 kgm/s
An object undergoes a change in momentum of +35 kgm/s due to an impact.
+35 kgm/s
A cart with mass 2m has a velocity v before it strikes another cart of mass 3m at rest. The two carts couple and move off together with a velocity of
(A) v/5 (B) 2v/5 (C) 2v/3 (D) (2/7) v
B. 2v/5
A 3kg red mass is moving rightward at 7.5 m/s when it collides with a 3kg blue mass initially moving 3 m/s to the left. Afterwards, the 3kg red mass is moving at 3 m/s to the left. The speed of the blue mass is:
7.5 m/s rightward
A ball with a mass of 0.50 kg and a speed of 6 m/s collides perpendicularly with a wall and bounces off with a speed of 4 m/s in the opposite direction. What is the magnitude of the impulse acting on the ball?
5 Ns
A 12gram mass is moving at 10 m/s
.12 kgm/s
A rightward force of 5kN is applied for 3ms.
+15Ns
An empty sled of mass M moves without friction across a frozen pond at speed vo. Two objects are dropped vertically into the sled one at a time: first an object of mass m and then an object of mass 2m. Afterward the sled moves with speed vf. What would be the final speed of the sled if the objects were dropped into it in reverse order?
(A) vf / 3
(B) vf / 2
(C) vf
(D) 2vf
C vf
A 10 kg bale of hay is moving to the right at 8 m/s.
A 0.09 kg bullet is fired from a rifle and heads to the left at 450 m/s. The bullet passes through the bale of hay emerging from the far side at 180 m/s.
What is the final velocity of the bale of hay due to this collision?
+5.57 kgm/s
A 50 kg bag of cats is in a 700 kg cannon resting. The cannon is fired. The bag of cats shoots out moving to the right at 350 m/s relative to the ground.
-25 m/s
A 5g pencil is moving to the left at 10 m/s
-.05kgm/s
A 7 kg cat moving at -10 m/s collides and sticks to a stationary rock that has a mass of 13 kg. The impulse acting on a cat is:
+45.5 Ns
Two football players with mass 75 kg and 100 kg run directly toward each other with speeds of 6 m/s and 8 m/s respectively. If they grab each other as they collide, the combined speed of the two players just after the collision would be
2 m/s
A 20 kg cannonball moving to the left at 10 m/s collides with a 5 kg cat moving at to the right at 5 m/s. Afterwards the 5 kg cat is moving at 19 m/s to the left.
What is the velocity of the 20 kg cannonball after the collision?
-4 m/s
Two carts are held together. Cart 1 is more massive than Cart 2. As they are forced apart by a compressed spring between them, which of the following will have the same magnitude for both carts.
Force
A 5kg cart is moving rightward at 5 m/s when it collides with a 10kg cart that is not moving. The two carts then move off with this momentum.
25kgm/s
A 20 kg bowling ball is initially moving at 8 m/s to the right when it is hit by a large mallet. Afterwards the ball is moving at 5 m/s to the left. The mallet was in contact with the ball for 150 milliseconds.
-260 Ns
A 5000 kg freight car moving at 4 km/hr collides and couples with an 8000 kg freight car which is initially at rest. The approximate common final speed of these two cars is
1.5 km/hr
Two objects having the same mass travel toward each other on a flat surface each with a speed of 1.0 meter per second relative to the surface. The objects collide head-on and are reported to rebound after the collision, each with a speed of 2.0 meters per second relative to the surface. Which of the following assessments of this report is most accurate?
(A) Momentum was not conserved therefore the report is false.
(B) If potential energy was released to the objects during the collision the report could be true.
(C) If the objects had different masses the report could be true.
(D) If the surface was inclined the report could be true.
B. If potential energy was released to the objects during the collision, the report could be true.
A student initially at rest on a frictionless frozen pond throws a 1 kg hammer in one direction. After the throw, the hammer moves off in one direction while the student moves off in the other direction. Which of the following correctly describes the above situation?
(A) The hammer will have the momentum with the greater magnitude
(B) The student will have the momentum with the greater magnitude
(C) The hammer will have the greater kinetic energy
(D) The student will have the greater kinetic energy
C. The hammer will have greater kinetic energy.