Pankaj Bhatt Solutions for Chapter: Work, Energy and Power, Exercise 2: QUESTIONS

A crane is used to lift 200 Kg load from ground to the height 20 m in 10 s. Efficiency of the crane is 70%. Calculate actual work done by the crane.

A crane is used to lift 200 kg load from ground to the height 20m in 10s. Efficiency of the crane is 70%. Calculate power of crane.

Power of a steamer is 10 H.P and it can move in a river with maximum speed of $7.46 {\mathrm{ms}}^{-1}$. What is the average viscous force by the river?

1000 kg of water falls per second from the water dam of height 30m. An electric generator at the bottom of the dam converts potential energy of water into electric energy. If efficiency of the generator is 90%, What is the electric power in watt, generated on the output of generator ?

Capacity of a water tank built at the height of 10 m is 200 litres. A lift pump of 2 kW is used to fill this tank. If the efficiency of the tank is 70%, calculate the time

A uniform chain of mass $\mathrm{m}$ and length $\mathrm{l}$ is lying on the table such that its one-fifth part is hanging from the edge of the table. What minimum work is required to lift this part of the chain on the table? 

The figure below shows a simple pendulum of mass 200 g and length 1 m. It is moved from position A to B. What is potential energy of the pendulum at B? Now pendulum is released from position B. What is its energy at A? What is the speed at A?

The figure below shows two masses of 1.5 kg and 1 kg attached with two weightless strings. If 1.5 kg mass is released from its position how much high 1 kg mass moves up? What is the speed of strike of 1.5 kg mass on the wall?