Advertisements
Advertisements
प्रश्न
State the energy changes which take place when A stone dropped from the top of a cliff reaches the ground after some time.
उत्तर
P.E (stone at the top of cloff) → K.E (falling stone) → P.E (stone at ground).
APPEARS IN
संबंधित प्रश्न
Derive a relationship between S.I. and C.C.S. unit of work
When does a force perform work?
A coolie is moving on a road with a luggage on his head. Does he perform work against the force of gravity? Give reason for your answer.
It takes 20 s for a person A of mass 50 kg to climb up the stairs, while another person B does the same in 15 s. Compare the Work done.
A water pump raises 50 litres of water through a height of 25 m in 5 s. Calculate the power of the pump required.
(Take g = 10 N kg-1 and density of water = 1000 kg m-3)
The power of a motor is 40 kW. At what speed can the motor raise a load of 20,000 N?
How much energy is gained by a box of mass 20 kg when a man, carrying the box waits for 5 minutes for a bus?
What do you mean by degradation of energy?
Why is the work done on an object moving with uniform circular motion zero?
P, Q and R are three forces which act as shown in fig.
The point O lies in the same plane. Given, P = Q = R = 10N
(i) Which force has the least moment about O? Give a reason.
(ii)Which force has the greatest moment about O? Give a reason.
Is power a scalar quantity?
(a) Define power and name its unit.
(b) A girl weighting 50 kg climbs up 60 steps each of 20 cm height in 5 minutes. Calculate the power developed.
How much energy is gained by a box of mass 20 kg when a man, runs carrying the box with a speed of 3 m/s-1 to catch the bus?
Can two agents, doing the same work, have different power?
Why is less effort needed to lift a load over an inclined plane as compared to lifting the load directly?
A man climbs a slope and another walks same distance on level road. Which of the two expends more energy and why?
A bucketful of water is to be drawn from a well ______ will be done when a ______ is applied to do this because there will be a ______ of water.
(displacement, work, force)
