A body of mass $ 0.1 kg $ moving with a velocity of $10 m/s$  hits a spring (fixed at the other end) of force constant $ 1000 N/m $ and comes to rest after compressing the spring. The compression of the spring is .............. $\mathrm{m}$

A block of mass $2\,\,kg$ is placed on a rough inclined plane as shown in the figure $(\mu  = 0.2)$ so that it just touches the spring. The block is allowed to move downwards. The spring will be compressed to a maximum of

The work done in joules in increasing the extension of a spring of stiffness $10\, N/cm$ from $4\, cm$ to $6\, cm$ is:

A spring of spring constant $ 5 \times 10^3$ $ N/m$  is stretched initially by $5\,cm$ from the unstretched position. Then the work required to stretch it further by another $5\,cm$ is .............. $\mathrm{N-m}$

A block is simply released from the top of an inclined plane as shown in the figure above. The maximum compression in the spring when the block hits the spring is :

Give the example of variable force. Write the formula of Hook’s law.