- #1
sankalpmittal
- 785
- 25
Confused regarding conservative and non conservative force...
Ok , so here is my explanation :
Suppose I take a box at a height 5m from a reference point upwards. Work done by gravity on the block is -mg(5) J. Upwards is taken as positive and downwards as negative. Then I again take that box 5m downwards to that reference point. Work done by gravity now is -mg(-5) = 5mg J. So net work done by gravity is -5mg+5mg = 0 J. So we find that work done by gravity depends only on initial and final position. So gravitation is a "conservative" force.
Now , I analyze force of push and pull.
Assume that the system is free from any other forces except that of push and pull.
Right is taken as positive and left as negative. I push the box 5m rightwards. Work done by the force of push is 5F J , where F is force of push. The I again take the box 5m leftwards. Work done by force of push is now (-F)(-5) = 5F J. Net work done is 10F J , and not zero. Many say its zero. Why ?
Thus I investigate that forces of push are non conservative. Am I correct ?
Ok , so here is my explanation :
Suppose I take a box at a height 5m from a reference point upwards. Work done by gravity on the block is -mg(5) J. Upwards is taken as positive and downwards as negative. Then I again take that box 5m downwards to that reference point. Work done by gravity now is -mg(-5) = 5mg J. So net work done by gravity is -5mg+5mg = 0 J. So we find that work done by gravity depends only on initial and final position. So gravitation is a "conservative" force.
Now , I analyze force of push and pull.
Assume that the system is free from any other forces except that of push and pull.
Right is taken as positive and left as negative. I push the box 5m rightwards. Work done by the force of push is 5F J , where F is force of push. The I again take the box 5m leftwards. Work done by force of push is now (-F)(-5) = 5F J. Net work done is 10F J , and not zero. Many say its zero. Why ?
Thus I investigate that forces of push are non conservative. Am I correct ?