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Question
A uniform metre rule of mass 100g is balanced on a fulcrum at mark 40cm by suspending an unknown mass m at the mark 20cm. What is the resultant moment now?
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Solution
Anticlockwise moment if mass m is moved to the mark 10 cm= 50 g x (40-10) cm = 50 x 30=1500g cm
Clockwise moment=100g x (50 - 40) cm= 1000 g cm
Resultant moment= 1500 g cm -1000 g cm= 500 g cm (anticlockwise)
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