A hemispherical bowl of radius $R$ is rotated about its axis of symmetry which is kept vertical with angular velocity $\omega $ . A small block is kept in the bowl. It remains stationary relative to the bowl surface at a position where the radius makes an angle $\theta $ with the vertical. The friction is absent. The value of $\theta $ is
A hemispherical bowl of radius $R$ is rotated about its axis of symmetry which is kept vertical with angular velocity $\omega $ . A small block is kept in the bowl. It remains stationary relative to the bowl surface at a position where the radius makes an angle $\theta $ with the vertical. The friction is absent. The value of $\theta $ is
- A
${\cos ^{ - 1}}\,\left( {\frac{g}{{R{\omega ^2}}}} \right)$
- B
${\sin ^{ - 1}}\,\left( {\frac{g}{{R{\omega ^2}}}} \right)$
- C
${\tan ^{ - 1}}\,\left( {\frac{g}{{R{\omega ^2}}}} \right)$
- D
none of these
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- [NEET 2019]
$A$ particle is moving in a circle :
$A$ particle is moving in a circle :