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Explain work energy theorem .

Answer» <html><body><p></p>Solution :For straightline motion : If body is <a href="https://interviewquestions.tuteehub.com/tag/moving-548882" style="font-weight:bold;" target="_blank" title="Click to know more about MOVING">MOVING</a> with initial velocity u and constantacceleration a , it acquired velocity v with displacement s <a href="https://interviewquestions.tuteehub.com/tag/thenfrom-2304784" style="font-weight:bold;" target="_blank" title="Click to know more about THENFROM">THENFROM</a> the third equationof motion , <br/> `v^(2) -u^(2) = 2as`<br/> multiplying `m/2 `on both sides of equation ,<br/> `1/2 mv^(2) -1/2 "mu"^(2) =mas ` <br/> `K_(f) -K_(i)=Fs [ :. ma =F] `<br/>For motion in three dimension :<br/> `v^(2) -u^(2) = 2vec(a) .vec(d)`<br/> where v = final velocity , u = <a href="https://interviewquestions.tuteehub.com/tag/intial-2746226" style="font-weight:bold;" target="_blank" title="Click to know more about INTIAL">INTIAL</a> velocity , `vec(a)` = constant acceleration and `vec(d)` = displacementMultiplying by `m/2 ` on both side of equation , <br/> ` 1/2 mv^(2) -1/2 "mu"^(2) = m vec(a) .vec(d)` <br/> `vec(F) .vec(d) ""[ :. mvec(a) = vec(F)] `<br/> The left hand side is the change in kinetic energy of body , whileright <a href="https://interviewquestions.tuteehub.com/tag/handis-481975" style="font-weight:bold;" target="_blank" title="Click to know more about HANDIS">HANDIS</a> the multiplication of force and the displacement .It is known as work and it is denoted by W. <br/> ` :. K_(f) - K_(i) = W and DeltaK = W ` <br/> This <a href="https://interviewquestions.tuteehub.com/tag/relation-1183220" style="font-weight:bold;" target="_blank" title="Click to know more about RELATION">RELATION</a> is known as work energy theorem . <br/> Note : If a body undergoes a displacement in the direction of net force , then work done on the body which is positive andthe speed and kineticenergy of body increases but if force and displacement are in opposite direction , then work done by the body which is negative and the speed and kinetic energy decreases .</body></html>


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