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Question
A block of mass 10 kg is suspended from two light spring balances, as shown in the following figure.
Options
Both the scales will read 10 kg.
Both the scales will read 5 kg.
The upper scale will read 10 kg and the lower zero.
The readings may be anything but their sums will be 10 kg.
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Solution
Both the scales will read 10 kg.
From the free-body diagram
K1x1 = mg = 10 x 9.8 = 98 N
K2x2 = K1x1
So, K1x1 = K2x2 = 98 N
Therefore, both the spring balances will read the same mass, i.e. 10 kg.
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