posted by Anonymous on .
two movers have to lift a refrigerator into a truck. one of the movers wants to life the refrigerator vertically, but the other mover wants to roll it up a ramp by applying a force parallel to the ramp. assume the height of the truck is 1.5m, the length of the ramp is 5.0m, and the weight of the refrigerator is 1200.0N. calculate the force and the total work required in each case. which method is easier?
The work required is the same in both cases, and equals the potential energy increase, 1200 N * 9.8 m/s^2*1.5 m = _ J
Less force is required when the ramp is used but the movers have to push the refrigerator farther. The vertical force required would be M g. When rollers and a ramp are used, friction should be negligible. Tho force required is the component of the weights down the ramp,
M g sin A = M g (1.5/5)
where A is the ramp angle.