A charged ball of mass 9 kg is suspended from a string in a uniform electric field

PHYSICS · Single correct · AP · Physics C: Electricity and Magnetism · Electric Charges Fields and Gauss's Law · Electric Charges Fields and Gauss's Law

Problem

A charged ball of mass 9 kg is suspended from a string in a uniform electric field E⃗=(3i^+5j^)×105 N/C\vec{E} = (3\hat{i} + 5\hat{j}) \times 10^5\,\text{N/C}. The ball is in equilibrium with θ=37∘\theta = 37^\circ. If direction of electric field is reversed, find the new equilibrium position of the ball. Give your answer in terms of angle made by string with vertical. Take g=10 m/s2g = 10\,\text{m/s}^2. (1) tan⁡−1(34)\tan^{-1}\left(\frac{3}{4}\right) (2) cot⁡−1(314)\cot^{-1}\left(\frac{3}{14}\right) (3) cot⁡−1(34)\cot^{-1}\left(\frac{3}{4}\right) (4) tan⁡−1(314)\tan^{-1}\left(\frac{3}{14}\right)

Related theory

Browse the problem library