A balanced lever has two weights on it, the first with mass 9 kg 9kg and the second with mass 4 kg4kg. If the first weight is 12 m12m from the fulcrum, how far is the second weight from the fulcrum?

1 Answer
Jul 1, 2018

The distance is =27m=27m

Explanation:

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The acceleration due to gravity is g=9.8ms^-2g=9.8ms2

The mass M_1=9kgM1=9kg

The mass M_2=4kgM2=4kg

The distance a=12ma=12m

Taking moments about the fulcrum

M_1gxxa=M_2gxxbM1g×a=M2g×b

So,

9gxx12=4gxxb9g×12=4g×b

b=(108g)/(4g)=27mb=108g4g=27m