$A$ sphere is placed rotating with its centre initially at rest ina corner as shown in figure $(a)$ & $(b)$. Coefficient of friction between all surfaces and the sphere is $\frac{1}{3}$. Find the ratio of the frictional force $\frac{{{f_a}}}{{{f_b}}}$ by ground in situations $(a)$ & $(b)$.

806-505

  • A

    $1$

  • B

    $\frac{9}{{10}}$

  • C

    $\frac{{10}}{9}$

  • D

    none

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