Momentum

Momentum

Solve the problems on your warm-up

Momentum

• p=m x v

• Units kg m/s

• An objects momentum changes whenever its speed of mass changes

Impulse

• Forces creating an impulse are often large

• How can we maintain an Impulse, while decreasing force?

• How can we relate this to energy transfer?

Momentum and impulse

• Momentum Can be summed

• impulse = force x time = change in momentum

• impulse is a vector that points in the same direction as the force

• An impulse changes an objects momentum

Conservation of Momentum

• Momentum conservation requires a total force of zero

• This is because if an external force acts on an object the momentum is changing

• Internal forces (forces in the system) have no effect and sum to zero

Conservation of momentum

• If the sum of external forces is zero momentum is conserved

• p_total= p₁+p₂=constant

• Individual momentums can change but the overall system will not

• Momentum conservation applies to all systems

• Momentum conservation results in recoil