Advertisements
Advertisements
प्रश्न
In loading a truck, a man lifts boxes of 100 N each through a height of 1.5 m.
If the man lifts 4 boxes per minute, at what power is he working?
(g = 10 m s−2)
उत्तर
Work done in lifting 4 boxes,
Work done
= (150) × (4) J
= 600 J
Time taken, (t) = 60 s
Now, we can calculate the power as,
Power = `"Work done"/"Time"`
So ,
Power = `600/60` W
= 10 W
So, the power is 10 W.
APPEARS IN
संबंधित प्रश्न
What is 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.
An electric heater is rated 1500 W. How much energy does it use in 10 hours?
Name the physical quantity whose unit is watt.
A body does 1200 joules of work in 2 minutes. Calculate its power.
Fill in the blank with suitable word :
Power is the rate of doing ___________.
The power output of an engine is 3kW. How much work does the engine do in 20 s?
Define power. Give the SI unit of 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)
An electric motor raises a load of 0.2 kg, at a constant speed, through a vertical distance of 3.0 m in 2 s. If the acceleration of free fall is 10 m/s2, the power in W developed by the motor in raising the load is :
