2The Third Law of MotionFor every action force, there is an equal and opposite reaction forceJumping on a trampoline cause the trampoline to exert an equal force upwardThe forces will always be equal but in opposite directions
3The Third Law of MotionAction and Reaction forces do not cancel each other outThis is because the force is equal but the force is being applied to different objects
4Rocket PropulsionIn aerospace engineering, the principal of action and reaction is very important.Newton's third law explains the generation of thrust by a rocket engineHot exhaust gas is produced through the combustion of a fuelThe hot exhaust gas flows through the rocket nozzle and is accelerated to the rear of the rocketIn re-action, a thrusting force is produced on the engine mount.
5Momentum A moving object has a property called momentum Momentum will have the direction of the velocityMomentum can be positive or negativeMomentum = mass (kg) x velocity (m/s)p = m x v
6What is the momentum of a car with a mass of 1300 kg traveling at a speed of 28 m/s?
7A baseball thrown by a pitcher has a momentum of 6. 0 kg m/s A baseball thrown by a pitcher has a momentum of 6.0 kg m/s. If the baseball’s mass is 0.15 kg, what is the baseball’s speed?
8What is the mass of a person walking at a speed of 0 What is the mass of a person walking at a speed of 0.8 m/s if their momentum is 52 kg m/s?
9Law of Conservation of Momentum The momentum of an object doesn’t change unless its mass, velocity or both changeThe total momentum of all objects in a collision will be the same before and after the collisionTotal momentum can’t be lost or created.Law of conservation of momentumIf a group of objects exerts forces only on each other, their total momentum shouldn’t change.