Chapter 1.7 - Momentum.

Question 1

Define momentum.

Answer 1

‘Momentum is defined as the product of mass and velocity, p = mv’.

Question 2

Define the principal of conservation of linear momentum.

Answer 2

‘For a system is which there are no external forces acting, the total momentum before the collision = total momentum after the collision ’.

Question 3

Two objects A and B collide and move away separately after the collision. State the equation you must utilise to solve a question on this system.

Answer 3

m_A u_A + m_B u_B = m_A v_A + m_B v_B

Question 4

Two objects A and B collide and move away together after the collision. State the equation you must utilise to solve a question on this system.

Answer 4

mAuA + mBuB = (mA + mB)v

Where v represents the common velocity after the collision.

Question 5

What is the difference between an elastic collision and an inelastic collision?

Answer 5

Elastic - k.e. is conserved.

Inelastic - k.e. is not conserved.

Question 6

What do you understand by a totally inelastic collision?

Answer 6

Both object collide, merge and move away together with a common velocity.

Question 7

Define impulse.

Answer 7

‘Impulse is the product of F x t’.

Question 8

DEFINE NEWTONS SECOND LAW IN TERMS OF MOMENTUM.

Answer 8

‘The rate of change of momentum of a body is directly proportional to the applied force and acts in the direction of the force’.