Summary Momentum and Impulse

MOMENTUM AND IMPULSE

MOMENTUM
All objects have mass, when an object is moving it has momentum
Momentum – the product of the mass and velocity of an object
P=mv
P = momentum
m = mass
m = velocity
Momentum is a vector  it has direction
Direction of momentum = direction of velocity



COLLISIONS
Collision – an isolated event in which two or more moving bodies exert forces
on each other over a relatively short time




When the club hits the ball according to newton’s third law the ball will exert a
force of equal magnitude in the opposite direction
The forces do not cancel each other out because they act on different bodies

, The force acting on an object during a collision is not constant




Therefore we use an average force



CHANGE IN MOMENTUM
In most cases velocity changes therefore momentum will change
ΔP = mvi – mvf
ΔP = m(vi – vf)
ΔP = change in momentum
m = mass
vi = initial velocity
vf = final velocity



NEWTONS SECOND LAW IN TERMS OF MOMENTUM
ΔPP
Fnet = ΔPt

Newton’s second law (in terms of momentum) – the net force acting on an
object is equal to the rate of change of momentum



APPLYING NEWTONS SECOND LAW