1. Momentum “Why can you stop a baseball traveling at 40 meters per second but not a car traveling at 1 meter per second?”

2. Momentum defined Measure of force needed to stop a moving object –Objects MUST be to have momentum Formula: –Momentum = mass x velocity p = momentum m = mass v = speed or velocity moving

3. Conservation of Momentum The total momentum of any group of objects remains the same unless an outside force acts on the objects. –What “outside” forces? Friction Heat Energy transfer –The momentum before a collision = momentum after after a collision

4. Newton’s Cradle

5. Momentum of train cars “Why can you stop a baseball traveling at 40 meters per second but not a car traveling at 1 meter per second?” –A baseball has a mass of 0.15 kilograms and the car has a mass of 1500 kilograms. What is the momentum of each object? –Formula: p = m ∙ v –Substitutions:p = 0.15kg ∙ 40 m/s –Answer with units: p= 6.0 kg ∙m/s –Formula: p = m ∙ v –Substitutions:p = 1500kg ∙ 1m/s –Answer with units: p= 1500 kg ∙m/s