Suppose you wish to compare the work done by pushing a box on rollers up a ramp to the work done if you lift the box straight up to the same final height.
a. What work is required to lift a 100N box (about 22 lbs) up to a table which is 1 m off the floor?
b. Let’s assume you also have a ramp available that makes an angle of 30° with the horizontal, as shown in the figure to the right. The ramp is 2 m long. The weight of the box (100 N) is due to the Earth pulling on the box. This 100 N is a force directed straight down. If you push it up a ramp, you are doing work against only the component of this weight along the ramp, which is 50 N, as shown in the diagram. How much work does it require to push the box up the ramp, assuming no friction?
c. Which situation (pushing up the ramp or lifting straight up) requires more work?
d. Which situation requires more force?
e. For which situation is the distance moved greater? f. What is the change in the gravitational potential energy of the box for each situation?
g. What advantage, if any, is there to using the ramp? Explain.

Transcribed Image Text:

-2 m 50 N 86.6 N 1m 30° 100 N SP6 Diagram