General Knowledge - Physics - Discussion

Pulling is easier than pushing.

The work is the same. Assuming initial velocity is equal to a final velocity in both situations (that is, they all are zero), then neither experienced a change in kinetic energy. I am assuming that they both are moved to the same height because this would be totally illogical and uninteresting, as well as unsolvable if they were not. Therefore work done by gravity in both is mg, they both are moved same distance vertically and gravity is opposing them the entire time, therefore, equal and opposite work had to be done. Now, considering friction, it's totally irrelevant. The stone is rolled, therefore friction is not doing work of any kind it is simply providing the torque necessary to cause the angular velocity to remain constant.

Since the perpendicular distance between stone and earth is less than slope. Hence force between stone and earth through the path of the slope is less than that between same through the perpendicular path by universal gravitational law. And the distance is more for slope and less for perpendicular for the same case. So, energy is constant ie, mgh. The coefficient of friction makes us easy to roll and increases power. I think C is correct.

Same amount of work, just over a greater distance. It's gotta be C.

Since in a simple machine effort * effort arm = load * load arm.

In this case it is effort * hypotenuse of the rt angled triangle = load * perpendicular.
But perpendicular<hypotenuse.
Therefore effort<load.

It is easy to roll down because the work is done when we throw it in vertical direction.

Whether you lift the stone or roll it up the slope ,stone gains potential energy equal to mgh .The stone gained this energy and by same amount you lost it ! Frictional force at the time of rolling up makes you to loose a little more of energy. You would have lost energy mgh when you lift it and mgh+ when you roll it up . Is it not better to lift then to roll it? Catch is here. There is mechanical advantage when you roll. Lever principle can be applied . Let the slope be 1/10. Rolling distance is 10 units whereas the lifting distance remains 1 unit . The effort is 1/10 now. You have a convenient comfort level ! In an ideal condition work done is same in both the cases. Rate of energy spending is less because you travel more distance. You spent less effort 1/10 and travelled 10 times more distance. Answer C is correct.

Work done in lifting is not more or less we feel it more due to the gravitational force acting on that object in same way we have to push it so no force required against gravity.

Here we have to consider the concept of inclined plane no doubt the amount of work done is same either we do it by rolling or pulling but one of the benefit is that gravitation force will be neglected.

More the slope less will be the effort.

D is the right answer that is true.