AnswersPhysics IConservation of Momentum

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Which are examples of perfectly inelastic collisions? Choose three correct answers.

A
bumper cars bumping off of each other
B
a plane landing on an aircraft carrier
C
two train cars coupling together
D
a cue ball hitting an eight ball and stopping
E
rain sticking to a window
F
a baseball bouncing off a bat
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Question text not available

Answer:

inelastic

3

Two identical carts travel at the same speed toward each other, and then a collision occurs. The graphs show the momentum of each cart as a function of time, both before and after the collision. Which graph shows a perfectly inelastic collision?

A
Image with description A graph with momentum on the y axis measured in kilogram meters per second and time on the x axis measured in seconds. There are no values on the axes. There are two curves on the graph the first starts above the x axis and is horizontal before curving downward toward the x axis labeled 2 m cart. The second curve starts below the axis, a smaller distance below as the first one was above, and is horizontal before curving upward toward and crosses the x axis and is labeled m cart. Where they meet is labeled Collision. Both curves meet above the axis at the same time and both go horizontal above the x axis for a time period labeled Combined carts.
B
Image with description A graph with momentum on the y axis measured in kilogram meters per second and time on the x axis measured in seconds. There are no values on the axes. There are two curves on the graph. The first starts above the x axis and is horizontal before curving downward to the x axis labeled 2 m cart. The second curve starts below the axis, the same distance below as the first one was above, and is horizontal before curving upward toward the x axis at the same time and labeled m cart. Where they meet is labeled Collision. Both curves meet at the x axis at the same time and are both on the x axis for a time period labeled Combined carts.
C
Image with description There is a graph with time in seconds on the x axis and the y axis is labeled P in kilogram meters per second. There is a red horizontal line that drops down below the x axis and is the farther away from the x axis and a horizontal line. A blue line is the mirror image starting below the x axis and ending above the x axis. The red line is labeled car A and a blue line labeled car B. At the point both graphs cross the x axis is labeled collision.
D
Image with description There is a graph with time in seconds on the x axis and the y axis is labeled P in kilogram meters per second. There is a red horizontal line that drops down below the x axis and is then farther away from the x axis and a horizontal line. A blue line is the mirror image starting below the x axis and ending above the x axis. The red line is labeled car A and a blue line labeled car B. At the point both graphs cross the x axis is labeled collision.
4

Which are examples of perfectly inelastic collisions? Choose three correct answers.

A
two train cars coupling together
B
rain sticking to a window
C
a cue ball hitting an eight ball and stopping
D
a baseball bouncing off a bat
E
bumper cars bumping off of each other
F
a plane landing on an aircraft carrier
5

A girl is standing still in the middle of a baseball field. The girl catches the baseball and begins to move in the same direction as the thrown ball. What type of collision is being described?

A
elastic, since the girl moves in the same direction as the thrown ball
B
inelastic, since the girl moves in the opposite direction of the thrown ball
C
inelastic, since the girl moves in the same direction as the thrown ball
D
elastic, since the girl moves in the opposite direction of the thrown ball
6

In a lab, two identical lab carts open paren m is equal to 1 point 0 kilograms close paren travel toward each other, each with a speed of 2 meters per second The cars collide, and one cart moves to the right with a speed of 3 meters per second and the other moves left with a speed of 2 meters per second What best explains the results of the experiment?

A
This proves the conservation of momentum since p sub i is equal to p sub f .
B
The increase in speed was due to the kinetic energy from one cart transferring to the other.
C
An additional mass was added to one cart, which explains the increase in speed.
D
This experiment did not occur in a closed system.
7

Question text not available

Answer:

thermal

8

For a movie stunt, an empty truck with a mass of 2000 kilograms goes 10 meters per second and runs into a stopped car of mass 1000 kilograms The truck then keeps moving and pushes the car along with it. If there are no other forces acting on this system, which best describes the results of the collision?

A
The speed of the combined vehicles is less than the initial speed of the truck.
B
The collision is perfectly elastic.
C
The momentum after the collision is greater than the momentum before the collision.
D
Kinetic energy stays the same.
9

A rubber bullet of mass m is fired from a rifle into a stationary block of 25 m The bullet remains in the block and both the bullet and the block move off with a common velocity. Assume this is an inelastic collision in a closed system. Which best describes the final momentum of the bullet/block?

A
The final momentum of the bullet/block is less than the initial momentum of the bullet.
B
The final momentum of the bullet/block is zero.
C
The final momentum of the bullet/block is equal to the initial momentum of the bullet.
D
The final momentum of the bullet/block is more than the initial momentum of the bullet.
10

Which equation best describes the law of conservation of momentum?

A
p sub i plus p sub f is equal to 0
B
p sub i is equal to p sub f
C
p sub i is greater than p sub f
D
p sub i is less than p sub f

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