Efficiency

A motor takes 5 kJ electrical energy to lift a 100 kg mass by 4 m (g=10). Efficiency?

A machine lifts a load of 500 N through a height of 10 m in 25 seconds. If the power input is 400 W,...

A rubber ball is dropped from a height of 2 m onto a hard floor and rebounds to a height of 1.28 m a...

A satellite moves in a perfectly circular orbit around the Earth under the gravitational pull direct...

A cyclist of total mass 70 kg rides up a slope inclined at 30 degrees to the horizontal at a steady ...

A small stone tied to a string is whirled in a vertical circle of radius 2 m. What is the minimum sp...

Two bodies of different masses possess the same magnitude of linear momentum while moving in a strai...

A ball is thrown vertically upward and returns to the same height from which it was launched on a wi...

A stone of mass 0.5 kg is dropped from rest at a height of 8 m above the ground. Ignoring air resist...

A weightlifter raises a barbell of mass 80 kg from the floor to a height of 2 m above the floor in 4...

A 2 kg lump of clay moving at 6 m/s strikes and sticks to a 4 kg block initially at rest on a fricti...

A car engine delivers a constant power of 50 kW while the car moves at a steady speed of 25 m/s alon...