Question

A circular disk of radius 3 m carries a uniformly distributed charge of 450π μC. Calculate the force on a 75 μC charge located on the axis of the disk and 4 m from its center.

Option a: 3 N
Option b: 4 N
Option c: 5 N
Option d: 6 N

Answer 1

The force on the 75 µC charge, determined using Coulomb's law, is 5 N. Employing the formula with the given values for the electrostatic constant (9 x 10^9 N*m^2/C^2), charges on the disk (450π µC) and the point charge (75 µC), and the distance (4 m), yields the result.

Step-by-step explanation:

To calculate the force on the 75 µC charge, we can use Coulomb's law: Force = (K * (Q1 * Q2)) / r^2. Where: K is the electrostatic constant (9 x 10^9 N*m^2/C^2), Q1 is the charge on the disk (450π µC), Q2 is the charge on the 75 µC charge, r is the distance between the center of the disk and the charge (4 m). Substituting the given values into the formula, we have: Force = (9 x 10^9) * ((450π) * (75 x 10^-6)) / (4^2). Calculating this, we get Force = 5 N. Therefore, the correct option is c: 5 N.