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lorasvet [3.4K]

3 years ago

15

A moving car initially has kinetic energy K. The car then moves in the opposite direction with four times its initial speed. Wha

t is the kinetic energy now

1 answer:

Liula [17]3 years ago

6 0

If initial speed was v, Kinetic energy was K = 1/2mv^2

When speed will be 4v, KE will be:

= 1/2 m (4v)^2

=1/2m 16 v^2

=16K

Now kinetic energy will become <em>1</em><em>6</em><em> </em><em>times</em><em> </em><em>of</em><em> </em><em>initial</em><em> </em><em>Kinetic</em><em> </em><em>Energy</em>

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Answer:

$A. 8.29\times 10^{-18}\ J$

Explanation:

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