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Question
Two identical springs of spring constant K are attached to a block of mass m and to fixed supports as shown in figure. When the mass is displaced from equilibrium position by a distance x towards right, find the restoring force
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Solution
When the mass is displaced from the equilibrium position by a distance x towards the right, the right spring gets compressed by x developing a restoring force kx towards the left on the block. The left spring is stretched by an amount of x developing a restoring force kx left on the block.
F1 = – kx (for left spring)
And F2 = – kx (for right spring)
Restoring force, F = F1 + F2 = – 2kx
∴ F = 2kx towards left.
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