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A sports car accelerations from zero to ...

A sports car accelerations from zero to a certain speed in `t` seconds. How long does it take for it to accelerate to twice that speed starting from rest, assuming the power of the engine to be constant (independent of velocity) and neglecting any resistance to motion?

A

(a)`sqrt(2)tsec`

B

(b)`2tsec`

C

(c)`3tsec`

D

(d)`4tsec`

Text Solution

Verified by Experts

The correct Answer is:
D
`Pt=(1)/(2)mv^(2)` `v` is doulbled `rArrt` is `4` times
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