A block of mass $m$ is pressed against a vertical surface by a spring of unstretched length $l$ . If the coefficient of friction between the block and the surface is $\mu $. Choose the correct statement.

830-638

  • A

    if spring constant $k = \frac{{2mg}}{{\mu d}}$, block will not be in equilibrium.

  • B

    if spring constant is $k = \frac{{2mg}}{{\mu d}}$, the normal reaction is $\frac{{mg}}{\mu }$

  • C

    in the part $(2)$ force of friction is $2mg$

  • D

    minimum spring constant $k_{min}$ to keep the block of mass $m$ in equilibrium is $\frac{{mg}}{{\mu d}}$

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  • [JEE MAIN 2022]