Q. 15

Expert-verified
Found in: Page 624

### Physics for Scientists and Engineers: A Strategic Approach with Modern Physics

Book edition 4th
Author(s) Randall D. Knight
Pages 1240 pages
ISBN 9780133942651

# A small glass bead has been charged to +20 nC. A small metal ball bearing 1.0 cm above the bead feels a 0.018 N downward electric force. What is the charge on the ball bearing?

The charge of the ball is

See the step by step solution

## Step 1: Content Introduction

We have two charged particles one of them has charge and another has a charge with a distance , the two particles exert forces on each other where the force decrease with the increase in the distance and increase with the increase in magnitude.

## Step 2: Content Explanation

Coulomb's law describes:

where K is the electrostatic constant and is given by . The charge of the bead is given by Convert unit into Coulomb by

now for

In nC, the charge of the ball is

## Step 3: Conclusion

The ball is above the bead and the force is downward, which means the glass bead attracts the ball downward, towards the bead, therefore, the two charges are not same. As the bead is positively charge, the charge of ball is negative.