Incomplete question. Missing part:
"it took him 10 seconds to move the couch. What was his power?"
Answer:
50 W
Explanation:
The power developed is given by:
[tex]P=\frac{W}{t}[/tex]
where
W is the work done
t is the time taken
In this problem,
W = 500 J
t = 10.0 s
Substituting into the equation, we find
[tex]P=\frac{500}{10}=50 W[/tex]
