Question

Certain weight is attached with a spring.It is pulled down and then released.It oscillates up and down.Its Kinetic Energy will be:

• A. maximum in the middle of the movement
• B. maximum at the bottom
• C. maximum just before it is released
• D. constant

Answer 1

The correct option is A maximum in the middle of the movement

As no external force is acting on the system so mechanical energy will be conserved.

potential energy + mechanical energy = constant

potential energy stored in the spring is given by $\frac{1}{2}K{x}^2$ so kinetic energy will be maximum when potential energy will be minimum, potential energy will be minimum when x is minimum in magnitude. i.e. x is zero.

so weight will have maximum kinetic energy when the block is in equilibrium position.i.e. $x_0=0$.

so best possible answer is A.