Here's how I approached this problem:
Since 1 W = 1 J/s, I set KE = 140 J.
Then, v^2 = KE/((.5)m) = 140/24.25 = 5.77
Then v = 2.4 m/s
But that's not the right answer.
What am I doing wrong?
<br>It looks like you're trying to use the work-kinetic energy theorem to solve this problem (i.e. that work done = change in kinetic energy) or something similar. But actually, power is the RATE OF CHANGE of work being done, or equivalently, the rate of change of energy. And if you just let someone move with a constant speed, they're ...