Question

Multiple Choice A leaky bag of sand weighs 50 \(\mathrm{n}\) . It is lifted from the ground at a constant rate, to a height of 20 \(\mathrm{m}\) above the ground. The sand leaks at a constant rate and just finishes draining as the bag reaches the top. Which of the following gives the work done to lift the sand to the top? (Neglect the bag.) (A) 50 \(\mathrm{J} \quad\) (B) 100 \(\mathrm{J}\) (C) 250 J (D) 500 \(\mathrm{J}\) (E) 1000 \(\mathrm{J}\)

Short answer

Therefore, the correct answer is (E) 1000 J.

Step-by-step solution

Determine the force

The force used to lift the sand is its weight, which is given as 50 \(\mathrm{n}\).

Determine the distance

The distance to which the sand is lifted is specified as 20 m.

Compute the work done

We compute the work done by multiplying Force and Distance. That is, \(W = \mathrm{Force} \times \mathrm{Distance} = 50\, \mathrm{n} \times 20\, \mathrm{m} = 1000\, \mathrm{J}\).