2 p = mv v Momentum p m p: momentum (kg ·m/s) m: mass (kg) quantity of motionp = mvmpvp: momentum (kg ·m/s)m: mass (kg)v: velocity (m/s)
3 v Momentum p m p = ? p = mv m = 280 kg p = (280 kg)(3.2 m/s) Find the momentum of a bumper car if it has a total mass of 280 kg and a velocity of 3.2 m/s.GIVEN:p = ?m = 280 kgv = 3.2 m/sWORK:p = mvp = (280 kg)(3.2 m/s)p = 896 kg·m/smpv
4 v Momentum p m p = 675 kg·m/s v = p ÷ m m = 300 kg The momentum of a second bumper car is 675 kg·m/s. What is its velocity if its total mass is 300 kg?GIVEN:p = 675 kg·m/sm = 300 kgv = ?WORK:v = p ÷ mv = (675 kg·m/s)÷(300 kg)v = 2.25 m/smpv
5 Conservation of Momentum Law of Conservation of MomentumThe total momentum in a group of objects doesn’t change unless outside forces act on the objects.pbefore = pafter
6 Conservation of Momentum One bumper car has a mass of 300 kg and a velocity of 2 m/s. A second bumper car has a mass of 500 kg and a velocity of 2 m/s. They collide, stick together and move off. What is their velocity after the collision?