Aparticle of mass 13 g and charge 45 μc is released from rest when it is 77 cm from a second particle of charge −11 μc. determine the magnitude of the initial ac- celeration of the 13 g particle.

Explanation:

First of all, we need to calculate the electric force exerted on the particle. This is given by:

where:

k is the Coulomb's constant

is the charge of the particle

is the charge of the second particle

is the initial separation between the particles

Substituting,

where the negative sign tells us that it is an attractive force. We can ignore it since we are only interested in the magnitude of the acceleration, which is given by

where

m = 13 g = 0.013 kg is the mass of the particle

Substituting, we find