Momentum and Collisions

Question 1

Equation for momentum

Answer 1

momentum = mass x velocity

Question 2

What is impulse?

Answer 2

Change in momentum (Ns)
impulse = mv - mu
impulse = force x time

Question 3

Find impulse between t=4 and t=8 of force = t²-6t+1

Answer 3

Integrate variable force with respect to time

Substitute in values for t

Question 4

What happens to momentum in collisions?

Answer 4

It is conserved

mUa + mUb = mVa + mVb

Question 5

What is the coefficient of restitution?

Answer 5

Ub - Ua

(seperation/approach)

Question 6

What does a coefficient of restitution value of 1 mean?

Answer 6

perfect elastic collision

momentum and KE is conserved

Question 7

What does a coefficient of restitution value of 0 mean?

Answer 7

perfect inelastic collision

momentum and all KE is lost

Question 8

What is the collision of a fixed object coefficient of restitution?

Answer 8

v = -eu

Question 9

In oblique impacts what happens to the velocity in the i direction?

Answer 9

Parallel to the wall
it doesn’t change
x=x

Question 10

In oblique impacts what happens to the velocity in the j direction?

Answer 10

Perpindicular to the wall
changes to -ey
y= -ey