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 moon is revolving around the earth in a circular path. How much work is done by the moon?
A machine raises a load of 750 N through a height of 16 m in 5 s. calculate:
- energy spent by machine,
- power at which the machine works.
When is the work done by a force on a body : (a) positive, (b) negative, and (c) zero?
Is the motion of moon around the earth in circular path an accelerated motion?
A coolie is pushing a box weighing 1500 N up an inclined plane 7.5 m long on to a platform, 2.5 m above the ground.
(i) Calculate the mechanical advantage of the inclined plane. (ii) Calculate the effort applied by the coolie.
(iii) In actual practice, the coolie needs to apply more effort than what is calculated. Give one reason why you think the coolie needs to apply more effort.
