On a calm day, a boat can go across a lake and return in time $T_0$ at a speed $V$. On a rough day, there is uniform current at speed $v$ to help the onward journey and impede the return journey. If the time taken to go across and return on the rough day be $T$, then $T / T_0$ is
On a calm day, a boat can go across a lake and return in time $T_0$ at a speed $V$. On a rough day, there is uniform current at speed $v$ to help the onward journey and impede the return journey. If the time taken to go across and return on the rough day be $T$, then $T / T_0$ is
- A
$1-v^2 / V^2$
- B
$\frac{1}{1-v^2 / V^2}$
- C
$1+v^2 / V^2$
- D
$\frac{1}{1+v^2 / V^2}$
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- [JEE MAIN 2021]