Advertisements
Advertisements
प्रश्न
Advertisements
उत्तर
This is because at each point of the circular path, the displacement is perpendicular to the force, which is directed towards the centre, along the radius.
APPEARS IN
संबंधित प्रश्न
An electron emitter must have _____________ work function and ___________ melting point.
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)
MULTIPLE CHOICE TYPE
In an electric cell which in use, the change in energy is from:
State two advantage of producing hydroelectricity.
A man lifts a mass of 10 kg from the floor to a shelf 4 meter high. If g = 10 ms-2, what is the work done?
If an electric bulb of 100 watt is lighted for 2 hours, how much electric energy would be consumed?
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.
An electric motor pump is 60% efficient and is rated 2.5 H.P. Calculate the maximum load it can lift through a height of 10m in 8 sec. (1 H.P. = 750 W).
Write the two main conditions are needed for work to be done?
