Q. 3

Expert-verified
Found in: Page 900

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

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

# 3. If you curl the fingers of your right hand as shown, are the electric fluxes in FIGURE Q31.3 positive or negative?

Part (a) The flux is negative.

Part (b) The flux is positive.

See the step by step solution

## Step 1. Introduction

Curl the right hand fingers around the loop with the thumb perpendicular to the surface of the loop. The thumb defines the positive direction.

If the electric field is directed along the direction of thumb then the flux through the surface is positive. If the electric field is directed opposite to the direction of thumb then the flux is negative.

## Part (a)

In figure (a),

Curl the right hand fingers around the loop the thumb is directed out of the page, and electric field is directed into the page. So, the flux is negative.

## Part (b)

In figure (b),

Curl the right hand fingers around the loop the thumb direction is left side, and electric field directed towards the left. So, the flux is positive.