A balanced lever has two weights on it, the first with mass 5 kg and the second with mass 35 kg. If the first weight is 9 m from the fulcrum, how far is the second weight from the fulcrum?

1 Answer
Dec 12, 2016

= 1.29m (3s.f.)

Explanation:

use turning moments:

M_1 * D_1 = M_2 * D_2

(M being mass of weight on lever, D being distance from fulcrum)

M_1 = 5kg
M_2 = 35kg

D_1 = 9m

find D_2:

M_1 * D_1 = 5 * 9 = 45
M_2 * D_2 = 35 * D_2 = 45

D_2 = (45/35) m

= (9/7)m

= 1.29m (3s.f.)