Question

Glen has raised a dumbbell of mass 5 kg to a height of 10 m above the ground. Calculate the work done by Glen? (Take $g=10m{s}^{-2}$)

• A. 500

Answer 1

The correct option is A 500
Mass, $m=5kg$
Displacement, $s=10m$
Acceleration due to gravity,$g=10m{s}^{-2}$

Work done, $W=Force\times displacement$
Force needed to lift the dumbbell is its weight (mg).

$W=F\times s$
$=mg\times s$
$=5\times 10\times 10$
$=500J$