# physics

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A 50.0kg cyclist on a 10.0kg bicycle speeds up from 5.0m/s to 10.0m/s , the total kinetic energy before acceleratingis 750, and after acceleratingis 3000, how much work is done to increase the kinetic energy of the cyclist and the bicycle

• physics -

Work for changing KE of cyclist+bicycle is
W=Δ KE= KE2 –KE1=
=3000-750 = 2250 J,
for the cyclist:
W1=ΔKE1 = m1•v2^2/2 – m1•v1^2/2 =
=50•100/2-50•25/2 =1875 J,
for the bicycle:
W2=ΔKE2 = m2•v2^2/2 – m2•v1^2/2 =
=10•100/2 - 10•25/2 =375 J

• physics -

I am 4 years in the future

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dude same

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me too

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We could also use:

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