Advertisements
Advertisements
Question
The power of a motor is 40 kW. At what speed can the motor raise a load of 20,000 N?
Advertisements
Solution
Power = 40 KW
Force = 20,000 N
Power = force × Speed
Speed =`"Power"/"Force"`
`=(40" KW")/(20,000)`
`=(40,000)/(20,000)`
= 2 m/s-1.
APPEARS IN
RELATED QUESTIONS
The S.I. unit of energy is .............
1 J = ______ calorie.
What do you mean by degradation of energy?
Fill in the blank with suitable word :
Work is measured as a product of __________ and __________
How much work is done by the gravitational force of earth acting on a satellite moving around it in a circular path? Give reason for your answer.
A block of mass 20 kg is pulled up a slope (fig.12) with a constant speed by applying a force of 500 N parallel to the slope. A and B are initial and final positions of the block.
(a) Calculate the work done by the force in moving the block from A and B.
(b) Calculate the potential energy gained by the block.
A girl of mass 40 kg runs a height of 80 stairs, each 25 cm high with a load of 20 kg on her head in 25 sec. If g is 10 m/s2, find:
(i) Gravitational force acting on the girl.
(ii) Work done by her.
(iii) Useful work done by her.
(iv) Her power in watt.
If a ball is dropped on the sloping roof of a house, it acquires ______ and falls on the ground. That is the transformation of ______ energy into ______ energy takes place.
(kinetic, potential, motion)
