5 SI unit of WorkJoule = Newton x meter(J) = N x m
6 A weight lifter lifts a 1600 newton barbell over his head A weight lifter lifts a 1600 newton barbell over his head. The barbell is lifted to a height of 2.0 meters. Calculate the work done. Work = Force x Distance
7 A student rows a boat across a still pond with a force of 72 newtons A student rows a boat across a still pond with a force of 72 newtons. The student travels a distance of 13 meters Calculate the work done. Work = Force x Distance
8 Involves timePowerHow fast is work done?Power = Work / timeWattsJoulessecondsLarge amounts of power are measured in kilowatts
9 Doing work faster requires more power. You can increase the amount of work done in a given time.ORYou can do a given amount of work in less time.
30 A woman drives her car onto wheel ramps to perform some repairs A woman drives her car onto wheel ramps to perform some repairs. If she drives a distance of 1.8 meters along the ramp to raise the car 0.3 meter, what is the ideal mechanical advantage (IMA) of the wheel ramps?IMA = Input DistanceOutput Distance
35 Part 3: TorqueThe drawing above represents a wrench. The left end of the wrench is attached to a bolt. Four equal forces of 100N are applied as indicated in the drawing.A. A 100N force would cause the most torque if it was placed at which letter above? (Why)B. What is the torque at AC. What is the torque at C
36 4. What is the boy weight in order for the see-saw to be in equilibrium?
37 5. How far is the boy from the fulcrum in the see-saw in equilibrium below?
38 How much work input is used to create work output EfficiencyEff. = Work output x 100%Work inputEx. Gas mileage = Miles drivenGallons of gas