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24 Nov 2008 22:00:02 IST

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why friction is non conservative force

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why friction is non conservative force

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pranav agrawal

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25 Nov 2008 10:11:17 IST

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ANY FORCE IS SAID TO BE CONSERVATIVE IF WORK DONE BY THAT FORCE IN A ROUND TRIP IS ZERO...

CONSIDER POINT A AND B. A BOX IS MOVED FROM A TO B AND BACK TO POINT A. WHEN IT IS MOVED TOWARDS POINT B FRICTIONAL FORCE ACTS TOWARDS A .... WHEN IT IS MOVED FROM B TO A FRICITONAL FORCE ACTS ITOWARDS B. HENCE IN BOTH THE MOVEMENT FRICTIOANAL FORCE DOES A -IVE WORK....
HENCE, WORK DONE IN ROUND TRIP IS NOT ZERO. HENCE FRICTIONAL FORCE NON- CONSERVATIVE.......

PLS RATE ........

Bhupesh Mohanty

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25 Nov 2008 16:44:31 IST

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an addon to the question Frictional force has electromagnetic origin and Electromagnetic forces are conservative in nature But Friction is NOT .. WHY ??

sachin

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25 Nov 2008 17:53:33 IST

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FRICTION IS A NON-CONSERVATIVE FORCE BECAUSE IN CASE OF CONSERVATIVE FORCE THE TOTAL ENERGY OF THE BODY REMAINS SAME,THAT IS ,IT JUST CHANGES FROM KINETIC TO POTENTIAL OR VICE VERSA.BUT IN CASE OF FRICTION THE TOTAL ENERGY OF BODY IS DISSIPATED TO SURROUNDING IN THE FORM OF HEAT .HENCE THE TOTAL ENERGY OF THE SYSTEM DECREASES,THAT IS, IF INITIALLY THE ENERGE OF SYSTEM WAS100 , NOW ITS HAS DECREASED TO SAY 90 JOULES. NOTE THAT THIS DECREASE IS BECAUSE NO SURFACE IN THIS WORLD IS TOTALLY FRICTIONLESS. FOR BETTER UNDERSTANDING OF FRICTION READ PAGE .NO 89 ARTICLE 6.5

Rizwan M

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25 Nov 2008 19:42:23 IST

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Well simply put reason behind friction according to modrn

theory is due to cold weld that is at atomic scale there is wander wallas

force or sum adhesive force acting they form temporary bond especially if there is uneven surface

so each time thay form a bond between uneven surfaces now force is required to break this bond

this is here energy is required.Now if u apply commn snse u can figure from abve exp why static fiction is more than kinetic

Srijita

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26 Nov 2008 18:01:54 IST

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friction is a NCF bcoz it takes out energy form the body and hence work done is not 0.Also it depends upon the path selected.

Ashutosh Sharma

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26 Nov 2008 19:12:36 IST

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@ Bhupesh Sir..

Electromagnetic forces do not change direction in a round trip, whereas Friction does.
Hence, Friction is a NCF. whereas electromagnetic forces are conservative..

Am I correct?

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