Advertisements
Advertisements
प्रश्न
A satellite revolves around the earth in a circular orbit. What is the work done by the force of gravity? Give reason.
Advertisements
उत्तर
The centripetal force, which generates the force of gravity, does no work. The satellites have accomplished nothing at all. This is due to the fact that the Earth is the satellite's centre of mass and that the displacement is always along the tangent to the circular route, or normal to the direction of force on the satellite. (θ = 90°)
Displacement of satellite is normal to the direction of force
where, O - Earth, S - Displacement, F - Force of gravity
W = F × S cos 90°
W = F × S × 0 = 0
APPEARS IN
संबंधित 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.)
A body, when acted upon by a force of 10 kgf, gets displaced by 0.5 m. Calculate the work done by the force, when the displacement is (i) in the direction of force, (ii) at an angle of 60° with the force, and (iii) normal to the force. (g = 10 N kg-1)
Is it possible that no transfer of energy may take place even when a force is applied to a body?
A mechanic can open a nut by applying a force of 200 N while using a lever handle of 50 cm length. How long handle is required if he wants to open it by applying a force of only 50 N?
Name the force needed for circular motion. What is the direction of the force?
An engine does 54,000 J of work by exerting a force of 6000 N on it. What is the displacement in the direction of the force?
In the following case write yes, if the work is being done and no if no work is being done.
A man trying to push a wall.
State the condition when the work done by the force is positive
