# A balanced lever has two weights on it, one with mass 1 kg and one with mass 4 kg. If the first weight is  9 m from the fulcrum, how far is the second weight from the fulcrum?

Apr 25, 2018

$2.25 \setminus \text{m}$

#### Explanation:

For a balanced lever, we have the following relationship:

${m}_{1} {d}_{1} = {m}_{2} {d}_{2}$

• ${m}_{1} , {m}_{2}$ are the masses of the two weights

• ${d}_{1} , {d}_{2}$ are their distances from the fulcrum

And so, we get:

$1 \setminus \text{kg"*9 \ "m"=4 \ "kg} \cdot {d}_{2}$

${d}_{2} = \left(9 \textcolor{red}{\cancel{\textcolor{b l a c k}{\text{kg""m")/(4color(red)cancelcolor(black)"kg}}}}\right)$

$= 2.25 \setminus \text{m}$