Question

In the following diagram `q' is a fixed point charge, A is small block of mass `m' and carrying a positive charge `Q'.
The coefficient of static friction between A and inclined plane is (0.1.) The minimum and maximum values of `q' required for `A' to be in static equilibrium are respectively ___

$(TakeK=\frac{1}{4\pi {ϵ}_0})$ (Assume wedge is fixed to ground and $tan370=\frac{3}{5}$)

• A. $\frac{26mg{d}^2}{43KQ},\frac{34mg{d}^2}{37KQ}$
• B. $\frac{26mg{d}^2}{43KQ},\frac{29mg{d}^2}{37KQ}$
• C. $\frac{34mg{d}^2}{43KQ},\frac{34mg{d}^2}{37KQ}$
• D. $\frac{26mg{d}^2}{43KQ},\frac{34mg{d}^2}{37KQ}$

Answer 1

The correct option is A $\frac{26mg{d}^2}{43KQ},\frac{34mg{d}^2}{37KQ}$

$K\frac{qQ}{d^2}cos{37}^{\circ }=mgsin{37}^{\circ }\pm f$
And $f=\mu N=\mu (mgcos{37}^{\circ }+K\frac{qQ}{d^2}sin{37}^{\circ })$