Momentum and Energy

Question 1

Define momentum

Answer 1

The product of the mass and velocity of the object.

Question 2

What causes change in momentum

Answer 2

moving objects collide with another, the velocity will have

Question 3

Define impulse

Answer 3

The product of the net force and the contact time

Question 4

Why are airbags important

Answer 4

Airbags increase the time over which the momentum of the body changes to zero. This decreases the force acting acting on the passenger since fnet = change in momentum therefore fnet is inversely proportional to time. therefor less chance of injury

Question 5

What happens to the change of momentum to objects that collide and separate after wards

Answer 5

According to Newtons 3rd when two objects collide the force exerted on both objects will be equal in magnitude. the time of contact will also be the same. therefore the change in momentum will be the same for both objects

Question 6

What happens to object moving vertically down

Answer 6

zero initial velocity

Question 7

What is an elastic collision

Answer 7

both momentum and kinetic energy is conversed

EKb=Eka

Question 8

What is an inelastic collision

Answer 8

only momentum is conserved and kinetic energy not conserved

ekafter greater than ek before

Question 9

what is an isolated system

Answer 9

system that has not net external acting on it