Kinetic energy as a function of time

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Prabs3257
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Homework Statement
a particle of mass m is subjected to a force F=F°(cos(t)i+sin(t)j) if initially the particle was at rest the kinetic energy of the particle as a function of time is fgiven by
Relevant Equations
a=dv/dt
I got acceleration by dividing force by m then replaced a by dv/dt and then integrated it to get velocity as a fxn of time and hence got kinetic energy but problem is my ans does not match with any option can someone please compare their ans
 
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  • Photo of a printed physics exam page with multiple-choice questions, including a block on a smooth surface with forces F1 = 2N and F2 = 20N, a projectile question, and a particle force question with options A to D, plus handwritten rough work below.
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PeroK said:
Can you show us what you did?
 
Attachments
  • Handwritten derivation on lined paper, rotated sideways: dv/dt = (f0/m)(cos t i + sin t j), then v = (f0/m)(sin t - cos t), then 1/2 mv^2 = (f0^2/2m)(sin t - cos t)^2, then K.E. = (f0^2/2m)(1 - sin 2t).
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PeroK said:
What velocity do you get at ##t=0##?
Ya i got my mistake and got the ans thanks
 
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