# A ball has a mass of 4.0 kg and is moving with a velocity of 15.0 km/h. The ball increased its speed to 30.0 Km/h, then the K.E of the ball will ?

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Steps please

Steps please

##### 1 Answer

Nov 26, 2017

OK, we need to find initial KE, final KE and the ratio between them (must be > 1) We’d normally have to start by putting velocity into SI units, but as we’re only after a ratio it won’t matter.

#### Explanation:

The KE has thus gone up by a factor of

So when velocity doubles, KE goes up by the square of that (in the equation there is a