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An astronaut floating freely in space de...

An astronaut floating freely in space decides to use his flash light as a rocket. He shines a 10 watt light beam in a fixed direction so that he acquires momentum in the opposite direction. If his mass is 80 kg , how long must he need to reach a velocity of `1ms^(-1)`

A

`9 sec`

B

`2.4 xx 10^(3)sec`

C

`2.4 xx 10^(6) sec`

D

`2.4 xx 10^(9) sec`

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The correct Answer is:
D
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