Question

Which requires more work: lifting a 100 kg sack a vertical distance of 2 m or lifting a 50 kg sack a vertical distance of 4 m?Explain.

Answer 1

Answer:

They both require the same amount of work.

Explanation:

Work is said to be done if the force applied to a body cause the boody to move through a distance. Mathematically;

Workdone = Force * Distance

Workdone = mass * acceleration due to gravity * Distance

For the 100kg sack lifted through a distance of 2m:

Workdone = 100 * 9.8 * 2

Workdone = 980 * 2

Workdone = 1960Joules

For 50kg sack lifted through a distance of 4m;

Workdone = 50 * 9.8 * 4

Workdone = 200 * 9.8

Workdone  = 1960Joules.

Since the workdone in carry both sack is the same, hence they both require the same amount of work.