A balanced lever has two weights on it, the first with mass 34 kg 34kg and the second with mass 68 kg68kg. If the first weight is 3 m3m from the fulcrum, how far is the second weight from the fulcrum?

1 Answer
May 16, 2017

The second weight 68kg68kg is 1.5m1.5m from the fulcrum.

Explanation:

The balanced lever is a simple scale in this configuration.
If the two weights balance each other then the distance from the fulcrum to each must be in proportion to the two weights.

That is: w_1*d_1=w_2.d_2w1d1=w2.d2

We were told that:

w_1=34kg; w_2=68kg; d_1=3mw1=34kg;w2=68kg;d1=3m

So: 34kg*3m=68kg*d_234kg3m=68kgd2

cancel(34kg)*3m=cancel(68kg)*d_2

2d_2=3m

d_2=1.5m