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Question Question 2(ii)
A uniform meter scale is in equilibrium as shown in the figure given below
Calculate the weight of the meter scale.
Let W gf be the weight of metre rule which acts downwards from 50 cm mark.
In equilibrium position, taking moments about fulcrum.
Anticlockwise moment = 40 x (30 - 5) = 40 x 25 = 1000 gf cm
Clockwise moment = W (50 - 30) = 20 W gf cm
∴ Using principle of moments:
Clockwise moment = anticlockwise moment
So, 20 W = 1000
W = = 50 gf
∴ Weight of the metre scale = 50 gf