lab 7

Question 1

The linear momentum of an object depends on its

Answer 1

The linear momentum of an object depends on its mass and velocity.

Question 2

The direction of the momentum is the same as the direction of the

Answer 2

velocity. For a stationary object (zero velocity), the linear momentum is zero.

Question 3

During collisions, the total momentum of the system of two or more objects is

Answer 3

During collisions, the total momentum of the system of two or more objects is conserved when the net external force on the system is zero. In our examples above, the external forces on each cart are the gravitational and the normal force, both have only vertical (y) components and add up to a zero net force along the y-direction. Since collisions happen over a very short time period, effects of friction can be neglected. Therefore, the net external force on our system is zero, and the total linear momentum is conserved. This means that the total momentum just before the collision is equal to the total momentum just after the collision.

Question 4

This statement represents the

Answer 4

the law of conservation of linear momentum.
If the toy cars in Example 5 above collide, the velocity of each car will change after the collision, but the total momentum of the system of two cars will remain the same, 0.335 m/s.

Question 5

When the momentum of one of the colliding objects decreases, the momentum of the other ball

Answer 5

increases by the same amount. This is true regardless of the type of collision, and even in cases where kinetic energy is not conserved.However, the final velocities of the cars after the collision depend on the type of the collision

Question 6

A collision is called elastic if the total kinetic energy of the system is

Answer 6

conserved.

Question 7

If the two colliding objects stick together after collision, then a

Answer 7

If the two colliding objects stick together after collision, then a perfectly inelastic collision has happened. After the collision, the two objects will move together with the same final velocity

Question 8

Most real collisions fall between

Answer 8

Most real collisions fall between elastic and perfectly inelastic. Energy is not conserved in inelastic collisions because part of the kinetic energy is converted to other forms of energy (e.g,, heat); however, the linear momentum is conserved in any type of collisions.

Question 9

Perfectly inelastic collision

Answer 9

PTotal conserved
KE total not conserved

Question 10

Elastic Colission

Answer 10

PTotal conserved
KE total conserved

Question 11

Inelastic Collision

Answer 11

PTotal conserved
KE total not conserved