Question
Thu November 03, 2011 By:

how can we derive the formula of kinetic energy?

Expert Reply
Fri November 04, 2011
THE PRODUCT OF FORCE AND THE DISTANCE COVERED IN THE DIRECTION OF FORCE IS EQUAL TO THE WORK DONE

IF WE REPRESENT WORK BY W,FORCE BY F AND DISTANCE BY S THEN
W=FxS ..........1
THEN ACCORDING TO IT
W=FxS
ACCORDING TO NEWTONS SECOND LAW OF MOTION
F=MA
PUTTING VALUE OF F INTO EQ 1
W=MAxS ..............2

ACCORDING TO THIRD EQ OF MOTION
2aS=Vf^2 - VI^2
IF VALUE OF VI IS V AND OF Vf IS 0
SO
2aS=0^2 - V^2
2aS=V^2
a=V^2/2S ..............3
PUTTING VALUE OF a IN EQ 2
W=M(V^2/2$)$
W=MV^2/2
OR W=1/2 MV^2
BECAUSE THIS WORK IS DUE TO TENSION SO
K.E=1/2 MV^2
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