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# Power = Force * velocity Question watch

1. "A rocket of mass 5800kg accelerates vertically from rest to a speed of 220ms^-1 in 25s. Calculate:"

a) "the gain of potential energy."
b) "the gain in kinetic energy."
c) "the power output of its engine, assuming no energy is wasted due to air resistance."

I'm only confused with part 'c' as my answers for the other two parts seem to be correct in the answers page of the textbook.
My answer for part 'c' is 10MW (using P=FV) but apparently it's supposed to be '12MW'.

(This question can be found on page 176 of the new AQA Physics book. I use Kerboodle for an online version of the book. The answer for this question is on page 567.)
2. I get 11.2MW, using P= mass * acceleration * velocity

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Updated: February 21, 2016
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