A balanced lever has two weights on it, one with mass #4 kg# and one with mass #2 kg#. If the first weight is # 9 m# from the fulcrum, how far is the second weight from the fulcrum?

1 Answer
Apr 1, 2016

Answer:

#18 "m"#

Explanation:

To balance the lever, the torque about the fulcrum must be zero.

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In this question, we have

  • #M_1 = 4 "kg"#
  • #a = 9 "m"#
  • #M_2 = 2 "kg"#

We want to find #b#.

Therefore,

#(4 "kg") * (9 "m") = (2 "kg") * b#

#b = frac{(4 "kg") * (9 "m")}{2 "kg"}#

#= 18 "m"#