Electrostatics Part 3

A small bob of mass 100 mg and charge +10µC is connected to an insulating string of length 1 m . It is brought near to an infinitely long non-conducting sheet of charge density ' σ ' as shown in figure. If string subtends and angle of 45∘ with the sheet at equilibrium the charge density of sheet will be.
{. Given ε0=8.85×10−12‌

F

m

and acceleration due to gravity, g=10‌

m

s2

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