00:02
So in this question, we have an object lying here and what you did, you just lifted the object and put it into the lift, sorry, not lift, in an al mirror.
00:17
You are just raising the object height h.
00:20
Here the kinetic energy was zero.
00:22
Here also it is sitting in the al mirror.
00:24
Kinetic energy is zero.
00:26
Here, potential energy was something which is u1.
00:29
Here potential energy was something which is u2.
00:32
So now you can see the potential energy has got changed and definitely there is a change in the total energy also.
00:39
So what is the amount of work that you did? so there was a force mg acting downwards and you have to apply a force in vertically upper direction which is also mg.
00:49
And now the force that you're applying is mg and the displacement that is happening in vertical direction is h...