Question

A car is running at a speed of 15 km h-' while another similar car is moving at a speed of 45 km - Find the ratio of their kinetic energies
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Answer 1

Answer:

It is like one car is moving with v speed and other with 2v speed because one is 15 km/h and other is 30 km/h .

K.E=0.5×m×v

2

K.E(1st)=0.5×m×v

2

K.E(2nd)=0.5×m×(2v)

2

Hence the ratio is 0.5×m×v

2

:0.5×m×(2v)

2

=1:4

Hence the ratio is 1:4.

Answer 2

Explanation:

The ratio of their kinetic energies is 1:9