A block of mass $30 \mathrm{kg}$ is being brought down by a chain. If the block acquires a speed of $40 \mathrm{cm} {\mathrm{s}}^{-1}$ in dropping down $2 \mathrm{m}$, find the work done by the chain during the process.

Consider the situation shown in the following figure. The system is released from rest and the block of mass $1 \mathrm{kg}$is found to have a speed $0.3 \mathrm{m} {\mathrm{s}}^{-1}$ after it has descended a distance of $1 \mathrm{m}$. Find the coefficient of kinetic friction between the block and the table.

In a children's park, there is a slide which has a total length of $10 \mathrm{m}$ and a height of $8.0 \mathrm{m}$ . A vertical ladder is provided to reach the top. A boy weighing $200 \mathrm{N}$ climbs up the ladder to the top of the slide and slides down to the ground. The average friction offered by the slide is three tenth of his weight. Find (a) the work done by the ladder on the boy as he goes up; (b) the work done by the slide on the boy as he comes down (c) the work done by the ladder on the boy as he goes up. Neglect any work done by forces inside the body of the boy.

Figure shows a particle sliding on a frictionless track which terminates in a straight horizontal section. If the particle starts slipping from point A, how far away from the track will the particle hit the ground?