Advertisements
Advertisements
प्रश्न
Write the formula for work done on a body when the body moves at an angle to the direction of force. Give the meaning of each symbol used.
उत्तर
When the body travels at an angle to the direction of force applied, then the work done will be equal to the product of the displacement and the component of force in the direction of displacement.
So, work done is given by the following formula:
W = (F) (S) cos θ
Where,
(W) - Work done
(F) - Force
(S) - Displacement
(θ) - Angle between force and displacement
APPEARS IN
संबंधित प्रश्न
Look at the activity below. Reason out whether or not work is done in the light of your understanding of the term ‘work’.
A sailboat is moving due to wind energy.
No work is done by a force if the body
State two factors on which the work done on a body depends.
A body, when acted upon by a force of 10 kgf, moves to a distance 0.5 m in the direction of force. Find the work done by the force. Take 1 kgf = 10 N.
When is work said to be done by a force?
A box of weight 150 kgf has gravitational potential energy stored in it equal to 14700 J. Find the height of the box above the ground. (Take g = 9.8 N kg-1)
How much work is done by the gravitational force of earth acting on a satellite moving around it in a circular path? Give reason for your answer.
Write an expression for work done by a force depends?
A boy pulls a box up to 10 m with a force of 5 kgf. Calculate the work done by him.
A bullet is of mass 'm' g and is moving with a velocity 'v' m/s. Find the kinetic energy of the bullet when
(a) The mass is doubled,
(b) The velocity is tripled.
Give an example
Light energy changes to electrical energy.
Give an example
Electrical energy changes to heat energy.
State larger units of power.
An electric motor pump is 60% efficient and is rated 2.5 H.P. Calculate the maximum load it can lift through a height of 10m in 8 sec. (1 H.P. = 750 W).
Look at the activity below. Reason out whether or not work is done in the light of your understanding of the term ‘work’.
Suma is swimming in a pond.
