# physics

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A racing dog is initially running at 20.0 , but is slowing down.
Q1. How fast is the dog moving when its kinetic energy has been reduced by half?
Q2. By what fraction has its kinetic energy been reduced when its speed has been reduced by half?

• physics -

ke=1/2 m v^2

v=sqrt 2KE/m

so when KE is halved, what is sqrt .5 ?

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