Momentum

Question 1

Linear momentum

Answer 1

A vector product of Mass and Velocity (¯ρ = m x ¯v).

Question 2

Net Force

Answer 2

Net Force on a body = rate of change of momentum Δm¯v.

Question 3

Impulse of a Force

Answer 3

Force x Δt = Δm¯v (symbols defined) Force x time for which the force acts
also, the area under a Force – Time graph.

Question 4

Principle of Conservation of momentum

Answer 4

In any direction, in the absence of forces, the total momentum of a system remains constant ; that is Momentum before = Momentum after.

Question 5

Perfect elastic collision (boing’s apart)

Answer 5

A collision in which no momentum or kinetic energy is lost

i.e. m1 u1 + m2 u2 = m1 v1 + m2 v2
½ m1 u12 + ½ m2 u22 = ½ m1 v12 + ½ m2 v22.

Question 6

Perfectly inelastic collision (sticks together)

Answer 6

A collision in which momentum is conserved but kinetic energy is not.

i.e. m1 u1 + m2 u2 = (m1 + m2) v1
½ m1 u12 + ½ m2 u22 = ½ (m1 + m2) v12.