Advertisements
Advertisements
प्रश्न
If 784 J of work was done in lifting a 20 kg mass, calculate the height through which it was lifted. (g = 9.8 m/s2)
Advertisements
उत्तर
Mass of the box (m) = 20 kg
Acceleration due to gravity (g) = 9.8 m/s2
Work done against gravity (W) = 784 J
Let the height above the ground be (h)
So, W = m × g × h
So, height can be calculated as,
`h = W/(m xx g)`
So ,
`h = 784/(20 xx 9.8) m`
= `784/196 m`
= 4 m
So the body is lifted to a height of 4 m.
APPEARS IN
संबंधित प्रश्न
State two factors on which the potential energy of a body at a certain height above the ground depends.
A body of mass m is moved from ground to a height h. If force of gravity on mass of 1 kg is g newton, find the potential energy stored in the body.
A spring is kept compressed by a small trolley of mass 0.5 kg lying on a smooth horizontal surface as shown in the adjacent fig. When the trolley is released, it is found to move at a speed v = 2 m s-1. What potential energy did the spring possess when compressed?
Two bodies A and B of equal masses are kept at heights of h and 2h respectively. What will be the ratio of their potential energies?
On what factors does the gravitational potential energy of a body depend?
Give one example each of a body possessing : (i) kinetic energy, and (ii) potential energy.
When a ball is thrown vertically upwards, its velocity goes on decreasing. What happens to its potential energy as its velocity becomes zero?
The energy, possessed by an object due to its position is called ______.
Which of the following is the example potential energy?
The potential energy is
