Advertisements
Advertisements
Question
Power P= ............ /time taken.
Advertisements
Solution
Power P = work done/time taken.
APPEARS IN
RELATED QUESTIONS
The blades of a windmill sweep out a circle of area A.
- If the wind flows at a velocity v perpendicular to the circle, what is the mass of the air passing through it in time t?
- What is the kinetic energy of the air?
- Assume that the windmill converts 25% of the wind’s energy into electrical energy, and that A = 30 m2, v = 36 km/h and the density of air is 1.2 kg m–3. What is the electrical power produced?
Rajan exerts a force of 150 N in pulling a cart at a constant speed of 10 m/s-1. Calculate the power exerted.
It takes 20 s for a girl A to climb up the stairs while girl B takes 15 s for the same job. Compare the power spent by then.
Name the physical quantity which is measured in calorie. How is it related to the S.I. unit of the quality?
Two equal masses m1 and m2 are moving along the same straight line with velocities 5 ms-1 and -9 ms-1 respectively. If the collision is elastic, then calculate the velocities after the collision of m1 and m2, respectively.
A quarter horse power motor runs at a speed of 600 r.p.m. Assuming 40% efficiency, the work done by the motor in one rotation will be
An engine pumps up 200 kg of water through a height of 20 m in 10 seconds. If the efficiency of the engine is 80%. Calculate the power of the engine.
Water falls from a height of 60 m at the rate of 15 kg/s to operate a turbine. The losses due to frictional force are 10% of the input energy. How much power is generated by the turbine? (g = 10m/s2)
A man is throwing bricks of mass 2 kg onto a floor from a height of 2 m. Bricks reach the floor at a speed `2sqrt(10)` m/s. Man throws 10 bricks in a minute. If the power of man is W watt then `3/10` W is equal to ______ W.
At any instant of time t, the displacement of any particle is given by 2t – 1 (SI unit) under the influence of force of 5N. The value of instantaneous power is (in SI unit):
