Archimedes and Heron are playing on a seesaw. Archimedes weighs 75 kg and Heron weighs 150 kg. If Heron is sitting 2 meters from the fulcrum, how many meters does Archimedes need to sit from the fulcrum?

Explanation:

Using the principle of moment to solve the problem. The principle states that the sum of clockwise moments is equal to the sum of anticlockwise moment.

Moment = force *perpendicular distance

Moment of Archimedes about the fulcrum = 75 * x  ... 1

x is the distance of Archimedes from the fulcrum

Moment of Heron about the fulcrum = 150 * 2 = 300kgm... 2

Equation 1 and 2 according to principle of moment to get x we have;

75x = 300

x = 300/75

x = 4metres

Archimedes need to sit 4m from the fulcrum

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