Advertisements
Advertisements
Question
No work is done by a force if the body
Options
moves in direction of force
does not move
moves in opposite direction
none of the these
Advertisements
Solution
does not move
APPEARS IN
RELATED QUESTIONS
When does a force perform work?
State the S.I. unit of energy.
Give reasons for the following A teacher moving around in the class is doing work but a child standing and reading a book is not doing any work.
Define 1 joule of work.
P, Q and R are three forces which act as shown in fig.

The point O lies in the same plane. Given, P = Q = R = 10N
(i) Which force has the least moment about O? Give a reason.
(ii)Which force has the greatest moment about O? Give a reason.
A girl of mass 50 kg runs up a flight of 40 steps in 20 seconds. If each step in 20 cm high, calculate the power developed by the girl. (g= 10 ms-2).
What is power? How do you differentiate kilowatt from kilowatt-hour? The Jog Falls in Karnataka state are nearly 20 m high. 2000 tonnes of waterfalls from it in a minute. Calculate the equivalent power if all this energy can be utilized? (g = 10 m s–2)
A uniform chain of length 2 m is kept on a table such that a length of 60 cm hangs freely from the edge of the table. The total mass of the chain is 4 kg. What is the work done in pulling the entire chain on the table?
