Question

To move a refrigerator of mass 170 kg into a house, a mover puts it on a dolly and covers the steps leading into the house with a wooden plank acting as a ramp. The plank is 9.6 m long and rises 3.3 m. The mover pulls the dolly with constant velocity and with a steady force 1400 N up the ramp. How much work does he perform? The acceleration of gravity is 9.8 m/s 2 . Answer in units of J.

Answer 1

Explanation:

The given data is as follows.

         mass (m) = 170 kg,        Distance (s) = 9.6 m

        Height (h) = 3.3 m,         Force (F) = 1400 N

First, we will calculate the work performed by her as follows.

                W = Fs

                    = $1400 N \times 9.6 m$

                    = 13440 J

Hence, minimal work necessary to lift the refrigerator is as follows.

               U = mgh

                   = $170 kg \times 9.8 \times 3.3 m$

                   = 5497.8 J

Therefore, we can conclude that he performed 5497.8 J of work.