A balanced lever has two weights on it, one with mass #3 kg# and one with mass #8 kg#. If the first weight is # 7 m# from the fulcrum, how far is the second weight from the fulcrum?

1 Answer
Aug 27, 2016

# 21/8# The force times distance on one side must balance the force times distance on the other side.

Explanation:

# M_1 xx D_1 = M_2 xx D_2#

The force x distance on one side of the fulcrum must equal the force times the distance on the other side of the fulcrum.

#M_1# = 3 kg

#D_1# = 7 m

#M_2# = 8kg

#D_2# = an unkown.

Subsitute the values into the equation and solve.

# 3 xx 7 = 8 xx D_2#

# 21/8 = D_2#

# 2 5/8 = D_2#