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

1 Answer
Dec 11, 2015

Answer:

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_1#=2kg mass at #l_1#=18m= #m_1l_1#=#2\times18#=#36#
let it be at a distance #x# from the fulcrum.
Moment due to the #m_2#=38kg mass at #l_2#= #x# distance=#38x#
Law of moments says-
#m_1 l_1=m_2 l_2#
#38x=36#
#x=\frac{36}{38}m=\frac{18}{19}m=0.94m#