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7 Jul 2009 17:14:19 IST

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derivation of f=ma from second law of motion

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derivation of f=ma from second law of motion

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Sagar Saxena

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7 Jul 2009 17:36:56 IST

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SECOND LAW OF MOTION SAYS FORCE APPLIED ON A BODY IS DIRECTLY PROPORTIONAL TO THE ACCELERATION PRODUCED

FORCE IS PROPORTIONAL TO ACCELERATION

f=ma

Pramod Gupta

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7 Jul 2009 18:42:05 IST

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acc. to 2nd law of motion the rate of change of momentum is propotional to the applied force& takes place in direction of force applied .
so if F acts on mass & increases its velocity frm u(intial) to v(final)then frm 2nd law of motion we derive
(mv-mu)/t=m (v-u/t)
so v-u/t = acc.
ma
f is inversly propotional to ma or we can tell tat
f=kma
but f is so defined that k=1
so again we derieve F =ma

ramyani chakrabarty

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7 Jul 2009 18:56:07 IST

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F =ma

CAN NEVER BE DERIVED.

It is restating " he rate of change of momentum.........etc "

Anirudh Kumar

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7 Jul 2009 19:19:13 IST

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force is defined as "rate of change of momentum "

in calculas

f = dp/dt

= d*m*v/dt

= mdv/dt

= ma

when all the terms are used in S.I units then value of constant k becomes 1

asha rao

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5 Jan 2012 07:50:59 IST

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the rate of change in momentum is directly proportional to the resultant external force acting on the body in the direction of force actin

so F = d(mv)/dt

F = Km dv/dt

since dv/dt= a

f = kma

k= 1 (proportionality constant )

F =ma

Vamshi Krishna

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14 Jan 2012 12:03:33 IST

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good asha rao.Can you explain why k has no units because we say 1N=1kgmpersecondsquare from F=ma

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