Two identical balls, each possessing a charge of 2.00 10⁻⁷ C and a mass of 100 g , are suspended by two 50 cm long insulating strings from a common point. The balls are initially held 5.0 cm apart and subsequently released. Determine the acceleration of one of the balls at the instant just after release.

Step-by-step solution

The forces acting on each ball are the electrostatic force F_e , the gravitational force mg , and the tension T in the string. Since the balls are released from rest, the initial velocity is zero. Thus, the radial acceleration is zero, and the net acceleration is purely tangential (perpendicular to the string). The electrostatic force between the balls is given by Coulomb's law: F_e = 1 4 ₀ q^2 d^2 F_e = 9 10^9 (2.00 10⁻⁷)^2 (0.05)^2 = 0.144 N The angle made by each string with the vertical is: = d/2 L = 2.5 cm 50