question_answer

A man carries a load of 50 kg through a height of 40m in 25s. If the power of the man is 1568 W, then find his mass.

Answer:

\[{{m}_{1}}=50\,kg\] \[h=40m\] \[g=9.8\,m/{{s}^{2}}\] \[t=25s\] \[P=1568\,w\] \[{{m}_{2}}=x=?\] \[P=\frac{mgh}{t}=\frac{({{m}_{1}}+{{m}_{2}})gh}{t}\] \[\Rightarrow 1568=\frac{(50+x)\times 9.8\times 40}{25}\] \[\Rightarrow 50+x=\frac{1568\times 25}{398}\] \[\therefore \,x=50g\]