Advertisements
Advertisements
प्रश्न
An object thrown at a certain angle to the ground moves in a curved path and falls back to the ground. The initial and the final points of the path of the object lie on the same horizontal line. What is the work done by the force of gravity on the object?
Advertisements
उत्तर
The object is displaced horizontally because the beginning and ultimate positions of an object thrown at a specific angle to the ground are on the same horizontal plane. The force of gravity on the object acts vertically downwards. Therefore, no labour is done.
APPEARS IN
संबंधित प्रश्न
A coolie does no work against the force of gravity while carrying a luggage on a road.
In which of the following cases, is work being done?
(i) A man pushing a wall.
(ii) a coolie standing with a load of 12 kgf on his head.
(iii) A boy climbing up a staircase.
1 J = ______ calorie.
What is the condition for a force to do work on a body?
The work done on an object does not depend on the :
Determine the amount of work done when an object is displaced at an angle of 30° with respect to the direction of the applied force.
What is the work done against gravity when a body is moved horizontally along a frictionless surface?
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.
