Advertisements
Advertisements
प्रश्न
When a body moves in a circular path, how much work is done by the body? Give reason.
(Hint: The body is acted upon by the centripetal force.)
Advertisements
उत्तर
When a body moves in a circular path, no work is done since the force on the body is directed towards the centre of circular path (the body is acted upon by the centripetal force), while the displacement at all instants is along the tangent to the circular path, i.e., normal to the direction of force.
APPEARS IN
संबंधित प्रश्न
If the power of a motor is 100 kW, at what speed can it raise a load of 50,000 N?
State and define the S.I. unit of work.
One horse power is equal to ______.
Name the quality which is measured in eV
State the principle of moments.
State the condition when the work done by a force is negative. Explain with the help of examples.
A pump is used to lift 600 kg of water from a depth of 75 m in 10s. Calculate:
- The work done by the pump,
- the power at which the pump works, and
- The power rating of the pump if its efficiency is 40%. (Take g = 10m s-2).
`["Hint" : "Efficiency" = "useful power"/"power input"]`
A machine raises a load of 750 N through a height of 16 m in 5 seconds. Calculate the power at which the machine works.
A man weighing 700 N runs up a flight of 15 steps, each 20 cm high, in 5 seconds. Calculate the power of the man.
