# How much work does it take to raise a 52 kg  weight 21 m ?

Dec 31, 2015

10712.52 Joules

#### Explanation:

The work done to raise an object from the ground is equal to its gravitational potential energy, given by:

$U = m g h$

where,

$U$ is the gravitational potential energy
$m$ is the mass of the object
$g$ is the acceleration due to gravity $= 9.81 \frac{m}{s} ^ 2$ for the earth
and $h$ is the height to which the object is raised.

Therefore, the work done,

$W = U = 52 \cdot 9.81 \cdot 21$

$= 10712.52 J$