Chapter 6 – Work, Energy and Power

How many 2.5kg bricks can a man carry up a staircase 3.6m high in one hour if he works at the average rate of 9.8 watt? How many 2.5kg bricks can a man carry up a staircase 3.6m high in one hour if he works at the average rate of 9.8 watt? October 28, 2020 [...]

A machine gun fires 6 bullets per second into a target the mass of each bullet is 3 gram and the speed 500 metre per second the power delivered to the Bullet is​ A machine gun fires 6 bullets per second into a target the mass of each bullet is 3 gram and the speed [...]

An engine pumps up 1 quintal of coal from a mine 100 m deep in 0.5s. If its efficiency is 60%. power of the engine? Take g=10 ms^2. An engine pumps up 1 quintal of coal from a mine 100 m deep in 0.5s. If its efficiency is 60%. power of the engine? Take g=10 [...]

A body of mass 2kg starts from rest and moves with uniform acceleration. It acquires a velocity 20ms^−1 in 4s. The power exerted on the body at 2s in watt is A body of mass 2kg starts from rest and moves with uniform acceleration. It acquires a velocity 20ms^−1 in 4s. The power exerted on [...]

A force of 7i+6k n makes a body move on a rough plane with a velocity of 3j+4k m/s. The power in watt is A force of 7i+6k n makes a body move on a rough plane with a velocity of 3j+4k m/s. The power in watt is October 28, 2020 Category: Chapter 6 - [...]

Two men with weights in the ratio 4:3 run up a staircase in time in the ratio 12:11. The ratio of power of the first to that of second is: Two men with weights in the ratio 4:3 run up a staircase in time in the ratio 12:11. The ratio of power of the first [...]

A motor drives a body along a straight line with a constant force. The power P developed by the motor must vary with time t as A motor drives a body along a straight line with a constant force. The power P developed by the motor must vary with time t as October 28, 2020 [...]

A particle moves with a velocity v=5i-3j+6k m/s- under the influence of a constant force F=10i+10j+20k N .The instantaneous power applied to the particle is. A particle moves with a velocity v=5i-3j+6k m/s- under the influence of a constant force F=10i+10j+20k N .The instantaneous power applied to the particle is. October 28, 2020 Category: Chapter [...]

A vehicle of mass M is moving on a rough horizontal road with a momentum P If the coefficient of friction between the tyres and the road be μ is then the stopping distance is . A vehicle of mass M is moving on a rough horizontal road with a momentum P If the coefficient [...]

A spring gun of spring constant 90 N/cm is compressed 12 cm by a ball of mass 16 g. If the trigger is pulled, the velocity of the ball is A spring gun of spring constant 90 N/cm is compressed 12 cm by a ball of mass 16 g. If the trigger is pulled the [...]