Question

Two girls each of weight 400N climb up a rope through a height of 8m. We name of the girls A and the other B. Girl A takes 20s while B takes 50s to accomplish this task
What is the power expended by each girl?​

Answer 1

$\huge\star{\underline{\mathtt{\red{A}\pink{n}\green{s}\blue{w}\purple{e}\orange{r}}}}$

1) Power expended by Girl A :-

Weight of the girl, mg = 400N

Displacement (height),h = 8m

Time taken,t = 20s

$power = \frac{work \: done}{time \: taken}$

= $\frac{mgh}{t}$

= $\frac{400n \times 8m}{20s}$

= $160w$

_____________________

2) Power expended by Girl B:-

Weight if the girl, mg = 400N

Displacement (height) ,h = 8m

Time taken (t) = 50s

=$power = \frac{work \: done}{time \: taken}$

=$\frac{mgh}{t}$

=$\frac{400n \times 8m}{50s}$

=$64w$

Answer 2

$\huge{\purple{\underline{\underline{\bf{\pink{Answer-1}}}}}}$

• Power expended by Girl A :-
• Weight of the girl, mg = 400N
• Displacement (height),h = 8m
• Time taken,t = 20s

power =$\frac{work \: done}{time \: taken}$

= $\frac{mgh}{t}$

= $\frac{400n \times 8m}{20s}$

= 160w

$\huge{\purple{\underline{\underline{\bf{\pink{Answer-2}}}}}}$

• Power expended by Girl B:-
• Weight if the girl, mg = 400N
• Displacement (height) ,h = 8m
• Time taken (t) = 50s

$power = \frac{work \: done}{time \: taken}$

=$\frac{mgh}{t}$

=$\frac{400n \times 8m}{50s}$

=64w