A balanced lever has two weights on it, the first with mass 2 kg 2kg and the second with mass 38 kg38kg. If the first weight is 18 m18m from the fulcrum, how far is the second weight from the fulcrum?

1 Answer
Dec 11, 2015

This problem can be easily solved by "Law of moments" which is just equating net torque on the system to zero.

Explanation:

Moment due to the m_1m1=2kg mass at l_1l1=18m= m_1l_1m1l1=2\times182×18=3636
let it be at a distance xx from the fulcrum.
Moment due to the m_2m2=38kg mass at l_2l2= xx distance=38x38x
Law of moments says-
m_1 l_1=m_2 l_2m1l1=m2l2
38x=3638x=36
x=\frac{36}{38}m=\frac{18}{19}m=0.94mx=3638m=1819m=0.94m