A balanced lever has two weights on it, the first with mass #7 kg # and the second with mass #4 kg#. If the first weight is # 3 m# from the fulcrum, how far is the second weight from the fulcrum?

1 Answer
Feb 3, 2016

Answer:

Weight 2 is #5.25m# from the fulcrum

Explanation:

Moment = Force * Distance

A) Weight 1 has a moment of #21# (#7kg xx3m #)

Weight 2 must also have a moment of #21#

B) #21/4 = 5.25m#

Strictly speaking the kg should be converted to Newtons in both A and B because Moments are measured in Newton Metres but the gravitational constants will cancel out in B so they were left out for simplicity's sake