Question

Consider the situation shown in The figure. The width of each plate is b. The capacitor plates are rigidly clamped in the laboratory and connected to a battery of emf $ϵ$. All surfaces are frictionless. The value of M for which the dielectric slab will stay in equilibrium is _____.

Answer 1

As shown in the figure, Force on dielectric due to electrostatic potential between capacitor is $\left(F\right)$.

$F=\frac{{\epsilon }_{0}b{V}^2}{2d}(k-1)$

if dielectric stay in equilibrium then

$F=mg$.

$mg=\frac{{\epsilon }_{0}b{V}^2}{2d}(k-1)$

$m=\frac{{\epsilon }_{0}b{V}^2}{2gd}(k-1)$