Advertisements
Advertisements
प्रश्न
Why does a spanner have a long handle?
उत्तर
A long handle facilitates increased torque with small application of force; hence a spanner has a long handle.
APPEARS IN
संबंधित प्रश्न
In each of the following a force, F is acting on an object of mass, m. The direction of displacement is from west to east, as shown by the longer arrow. Observe the diagrams carefully and state whether the work done by the force is negative, positive or zero.
What is the work done by the moon when it revolves around the earth?
Derive a relationship between S.I. and C.C.S. unit of work
Work done by a boy depends on the time in which he does work.
Define 1 joule of energy.
What are the quantities on which the amount of work done depends? How are they related to work?
A boy throws a rubber ball vertically upwards. What type of work, positive or negative, is done : by the force applied by the boy?
(a) by the force applied by the boy?
(b) by the gravitational force of earth?
Give one example each in which a force does (a) positive work (b) negative work, and (c) zero work.
When is the work done by a force on a body : (a) positive, (b) negative, and (c) zero?
Fill in the boxe to show the corresponding energy transformation.
Give an example
Electrical energy changes to heat energy.
How is horse power related to the S. I. unit of power?
A water pump raises 50 kg of water through a height of 25 m in 5s. Calculate the power supplied by the pump (Take: g = 10 N kg−1).
Look at the activity below. Reason out whether or not work is done in the light of your understanding of the term ‘work’.
An engine is pulling a train.
State whether work is done or not, by writing yes or no, in the following case:
A man pushes a wall.