Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 24: Q. 4 (page 682)

The electric field is constant over each face of the cube shown in FIGURE EX24.4. Does the box contain positive charge, negative charge, or no charge? Explain.

Short Answer

Expert verified

The box has a negative charge.

Step by step solution

01

Step 1. Given Information

Over each face of the cube illustrated, the electric field is constant.

02

Step 2. Is there a positive charge, a negative charge, or no charge in the box?

According to Gauss's law ∮E→·dA→=Qε0,

Here E is the electric field, A is the area, Q is the charge and ε0is a constant

Now apply Gauss's law, to get

Qε0=∮E→·dA→=(-15-20-15+20+15+10)A=-5A

So, let have chargeQ=5Aε0<0

⇒The box has negative charge

Gauss's law for electric flux is used to determine the charge of the box.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

The cube in FIGURE EX24.7 contains negative charge. The electric field is constant over each face of the cube. Does the missing electric field vector on the front face point in or out? What strength must this field exceed?

A spark occurs at the tip of a metal needle if the electric field strength exceeds 3.0×106N/C, the field strength at which air breaks down. What is the minimum surface charge density for producing a spark?

Newton’s law of gravity and Coulomb’s law are both inversesquare laws. Consequently, there should be a “Gauss’s law for gravity.” a. The electric field was defined as E u = F u on q /q, and we used this to find the electric field of a point charge. Using analogous reasoning, what is the gravitational field g u of a point mass?

Write your answer using the unit vector nr, but be careful with signs; the gravitational force between two “like masses” is attractive, not repulsive. b. What is Gauss’s law for gravity, the gravitational equivalent of Equation 24.18? Use ΦG for the gravitational flux, g u for the gravitational field, and Min for the enclosed mass. c. A spherical planet is discovered with mass M, radius R, and a mass density that varies with radius as r = r011 - r/2R2, where r0 is the density at the center. Determine r0 in terms of M and R. Hint: Divide the planet into infinitesimal shells of thickness dr, then sum (i.e., integrate) their masses. d. Find an expression for the gravitational field strength inside the planet at distance r 6 R.

A tetrahedron has an equilateral triangle base with20-cm-long edges and three equilateral triangle sides. The base is parallel to the ground, and a vertical uniform electric field of strength 200N/C passes upward through the tetrahedron. a. What is the electric flux through the base? b. What is the electric flux through each of the three sides?

An early model of the atom, proposed by Rutherford after his discovery of the atomic nucleus, had a positive point charge +Ze (the nucleus) at the center of a sphere of radius R with uniformly distributed negative charge -Ze. Z is the atomic number, the number of protons in the nucleus and the number of electrons in the negative sphere. a. Show that the electric field strength inside this atom is

Ein=Ze4πϵ01r2-rR3

b. What is E at the surface of the atom? Is this the expected value? Explain.

c. A uranium atom has Z = 92 and R = 0.10 nm. What is the electric field strength at r = 1 2 R?
See all solutions

Recommended explanations on Physics Textbooks

Electromagnetism

Read Explanation

Linear Momentum

Read Explanation

Fundamentals of Physics

Read Explanation

Turning Points in Physics

Read Explanation

Physics of Motion

Read Explanation

Waves Physics

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free