# A balanced lever has two weights on it, the first with mass 4 kg  and the second with mass 32 kg. If the first weight is  5 m from the fulcrum, how far is the second weight from the fulcrum?

Feb 26, 2016

$\textcolor{b r o w n}{\text{The second weight is 40 metres from the fulcrum}}$

#### Explanation:

The way to compare the two sides for 'Equilibrium' (balanced) is to compare 'moment arms' using force times distance

So we end up with $\left(32 \times 5\right) K g m = \left(4 x\right) K g m$

Divide both sides by 4 giving:

$\frac{32 \times 5}{4} = x$

$x = 40$ but $x$ is in metres so we have:

$\textcolor{b r o w n}{\text{The second weight is 40 metres from the fulcrum}}$