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(a) How can you visualise a power of 1 k...

(a) How can you visualise a power of `1 k W` ?
(b) Describe the energy changes that take place when you stop your car by using the brakes.

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(a) One watt of power raises a mass of `1 kg` through a height of `0.1 m` each second (i.e with a velocity of `0.1 m//s`)
Note that `P = F_v = (10 N)(0.1 m//s) = 1 W`
(b) The kinetic energy of the car is converted into thermal energy in the brakes.
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