Advertisements
Advertisements
प्रश्न
A boy weighing 25 kgf climbs up from the first floor at height 3 m above the ground to the third floor at height 9m above the ground. What will be the increase in his gravitational potential energy? (Take g = 10 N kg -1)
Advertisements
उत्तर
Force of gravity on boy = mg = 25 × 10 = 250N
Increase in gravitational potential energy = Mg (h2-h1)
= 250 × (9−3)
=250 × 6 = 1500 J
संबंधित प्रश्न
State two conditions when no work is done by a force.
MULTIPLE CHOICE TYPE
In an electric cell which in use, the change in energy is from:
State the SI unit of work.
When do we say that work is done? Write the formula for the work done by a body in moving up against gravity. Give the meaning of each symbol which occurs in it.
Its moment of a force scalar or a vector quantity?
Look at the activity below. Reason out whether or not work is done in the light of your understanding of the term ‘work’.
A green plant is carrying out photosynthesis.
