It takes $20$ $s$ for a girl $A$ to climb up the stairs while girl $B$ takes $15$ $s$ for the same job. Compare: $(i)$ the work done and $(i i)$ the power spent by them.

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Solution

$(1) .$ For work done: work does not depend on time so work will be same for both.
$\frac{W_{1}}{W_{2}} = \frac{1}{1}$
$W_{1} : W_{2} :: 1 : 1$
$(2) .$ Power spent will be time dependent
$P = \frac{W}{t}$
$\frac{P_{1}}{P_{2}} \propto \frac{t_{2}}{t_{1}}$
$\Rightarrow P_{1} : P_{2} :: 3 : 4$

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It takes 20 s for a girl A to climb up the stairs while girl B takes 15 s for the same job. Compare: (i) the work done and (ii) the power spent by them.

(1). For work done: work does not depend on time so work will be same for both.W1W2=11W1:W2::1:1(2). Power spent will be time dependentP=WtP1P2∝t2t1⇒P1:P2::3:4

It takes $20$ $s$ for a girl $A$ to climb up the stairs while girl $B$ takes $15$ $s$ for the same job. Compare: $(i)$ the work done and $(i i)$ the power spent by them.

$(1) .$ For work done: work does not depend on time so work will be same for both.
$\frac{W_{1}}{W_{2}} = \frac{1}{1}$
$W_{1} : W_{2} :: 1 : 1$
$(2) .$ Power spent will be time dependent
$P = \frac{W}{t}$
$\frac{P_{1}}{P_{2}} \propto \frac{t_{2}}{t_{1}}$
$\Rightarrow P_{1} : P_{2} :: 3 : 4$