Advertisements
Advertisements
Question
A girl weighting 50 kg climbs up 60 steps each of 20 cm height in 5 minutes. Calculate the power developed.
Advertisements
Solution
Given: mass = 50kg
Total height traveled = 60 × 20 cm
= 1200 cm
= 12m
g = 10 ms−2
time taken = 5 min
= 5 × 60 s
= 300 s
Work done = mgh
= 50 × 10 × 12
= 6000J
Power = `"work done"/"time taken"`
= `6000/300`
= 20 watt
APPEARS IN
RELATED QUESTIONS
Explain briefly why the work done by a fielder when he takes a catch in a cricket match is negative.
An electron emitter must have _____________ work function and ___________ melting point.
Power spent by a body depends on the time for which it does work.
The S.I. unit of work is
Give two examples of couple actions in our daily life.
Distinguish between work and power.
A cricket ball is thrown up from the earth's surface. What happens to its P.E.
(a) during the motion
(b) at the highest point?
A bullet is of mass 'm' g and is moving with a velocity 'v' m/s. Find the kinetic energy of the bullet when
(a) The mass is doubled,
(b) The velocity is tripled.
What are the advantages and disadvantages of using solar cells for producing electricity?
A ______ should act on an object.
