Question

Question #cd757

Answer 1

When the object reaches the bottom of the inclined plane,its total energy is purely kinetic,considering horizontal to be the reference level.

And,the energy value is `1/2 ×0.25×5^2=3.125J` (using `1/2mv^2`)

Now,total energy on top of the inclined plane was purely potential energy as the object was at rest,and its value was `mgh` (where, `h` is the height of the plane)

As, `h/l = sin 30` so, `h=l/2=6/2=3m` (`l` is the length of the inclined plane)

So,total energy at the beginning of the journey was `0.25×9.81×3=7.36 J`

So,this decrease in total energy value suggests that it must have been utilized to overcome the frictional force,

And the value is `(7.36 - 3.125)=4.24 J`