Advertisements
Advertisements
Question
What is the work done against gravity when a body is moved horizontally along a frictionless surface?
Advertisements
Solution
When a body is moved horizontally along a frictionless surface, the work done against gravity is zero because the direction of motion of the body is perpendicular to the direction of the gravitational force.
APPEARS IN
RELATED QUESTIONS
When do we say that work is done?
A man lifts a mass of 20 kg to a height of 2.5 m. Assuming that the force of gravity on 1 kg mass is 10 N, find the work done by the man.
Express joule in terms of erg.
1 J = ______ calorie.
Is power a scalar or a vector quantity?
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.
A ______ should act on an object.
