Answer:
Q = 1.52 X 10⁻⁷ C.
Explanation:
String is inclined at 10 degree with the vertical so the vertical component of T will balance the weight and the horizontal component will balance the force of repulsion F.
T Cos 10 = mg
T Sin 10 = F
Tan 10 = F / mg
F = mg Tan 10
= 10⁻³ x 9.8 x .176
= 1.728 x 10⁻³ .
Force of repulsion F = K Q² / R²
Distance between two charges = 2 x 1 x sin 10
= .347 m
1.728 X 10⁻³ = [tex][tex]\frac{9\times10^9\times Q^2}{(0.347)^2}[/tex][/tex]
Q² = 2.31 X 10⁻¹⁴
Q = 1.52 X 10⁻⁷ C.
