Advertisements
Advertisements
प्रश्न
What is power?
Advertisements
उत्तर
Power is the rate of doing work or the rate of transfer of energy. If W is the amount of work done in time t, then power is given by the expression,
The rate of doing work or energy conversion rate is called power.
Power = `"Work" /"time"`
or P = `W/t`
Where, P = Power
w = Work
t = Time
APPEARS IN
संबंधित प्रश्न
Define average power.
A person holds a bundle of hay over his head for 30 minutes and gets tired. Has he done some work or not? Justify your answer.
Find the energy in joules consumed in 10 hours by four devices of power 500 W each.
A load of 100 kg is pulled up by 5 m. Calculate the work done. (g = 9.8 m/s2)
A body of mass 100 kg is lifted up by 10 m. Find :
(i) the amount of work done
(ii) potential energy of the body at that height (value of g = 10 m/s2)
Define kilowatt-hour.
Fill in the blank with suitable word :
Power is the rate of doing ___________.
A man weighing 500 N carried a load of 100 N up a flight of stairs 4 m high in 5 seconds. What is the power?
A boy weighing 40 kg carries a box weighing 20 kg to the top of a building 15 m high in 25 seconds. Calculate the power. (g = 10 m/s2)
In loading a truck, a man lifts boxes of 100 N each through a height of 1.5 m.
How much work does he do in lifting one box?
