MCQ
A man does a given amount of work in $10s.$ Another man does the same amount of work in $20s.$ The ratio of the output power of the first man to that of second man is
- A$1$
- B$1 : 2$
- ✓$2 : 1$
- D$3 : 1$
✓
Answer
Correct option: C.
$2 : 1$
Since, $\text{P}=\frac{\text{W}}{\text{t}}$
So, if $W$ is constant, than $\text{P}\propto\frac{1}{\text{t}}$
i.e. $\frac{\text{P}_1}{\text{P}_2}=\frac{\text{t}_2}{\text{t}_1}=\frac{20}{10}$
$\Rightarrow\frac{\text{P}_1}{\text{P}_2}=\frac{2}{1}$
$P_1 : P_2$
$= 2 : 1$
So, if $W$ is constant, than $\text{P}\propto\frac{1}{\text{t}}$
i.e. $\frac{\text{P}_1}{\text{P}_2}=\frac{\text{t}_2}{\text{t}_1}=\frac{20}{10}$
$\Rightarrow\frac{\text{P}_1}{\text{P}_2}=\frac{2}{1}$
$P_1 : P_2$
$= 2 : 1$
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