A balanced lever has two weights on it, the first with mass 3kg and the second with mass 24kg. If the first weight is 9m from the fulcrum, how far is the second weight from the fulcrum?

1 Answer
Dec 30, 2015

r=1.125m

Explanation:

Let m1=3kg m2=24kg
Let W1 and W2 be the weights of m1 and m2 respectively.
W1=m1g=39.8=29.4N
W2=m2g=249.8=235.2N

Since the lever is balanced so both the torques produced by W1 and W2 should be equal.

Let the mass m2 be at a distance from r from the fulcrum.

Let τ1 and τ2 be the torques produced by W1 and W2 respectively.
τ1=τ2
W19=W2r
29.49=235.2r
r=29.49235.2=1.125m
r=1.125m
Hence the second weight is at a distance of 1.125m from the fulcrum.