A car is moving with a constant speed of $20\,m / s$ in a circular horizontal track of radius $40\,m$. A bob is suspended from the roof of the car by a massless string. The angle made by the string with the vertical will be : (Take $g =10$ $\left.m / s ^2\right)$
JEE MAIN 2023, Medium
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$T \cos \theta= mg$
$T \sin \theta=\frac{ mv ^2}{ R }$
$\tan \theta=\frac{ v ^2}{ Rg }$
$\tan \theta=\frac{20^2}{40 \times 10}$
$\tan \theta=1$
$\Rightarrow \theta=\frac{\pi}{4}$
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