Advertisements
Advertisements
प्रश्न
A force of 7 N acts on an object. The displacement is, say 8 m, in the direction of the force (see the given figure). Let us take it that the force acts on the object through the displacement. What is the work done in this case?
Advertisements
उत्तर
When a force F acts on an object to displace it through a distance S in its direction, then the work done to the body by the force is given by:
Work done = Force × Displacement
W = F × S
Where,
F = 7 N
S = 8 m
Therefore, work done, W = 7 × 8
= 56 Nm
= 56 J
APPEARS IN
संबंधित प्रश्न
Give reasons for the following. No work is done if a man is pushing against a wall.
A person of mass 50 kg climbs a tower of height 72 metres. Calculate the work done. (g = 9.8 m s−2).
Complete the following sentences:
The SI unit of work is ....... and of power is .......
Name the type of energy possessed by a
(i) stretched catapult (ii) hot iron
(iii) wound up clock
A body does 20 J of work in 10 s. What is its power?
(a) Define power and name its unit.
(b) A girl weighting 50 kg climbs up 60 steps each of 20 cm height in 5 minutes. Calculate the power developed.
Give an example
Electrical energy changes to heat energy.
Look at the activity below. Reason out whether or not work is done in the light of your understanding of the term ‘work’.
A donkey is carrying a load on its back.
