Physics: Principles with Applications
Physics: Principles with Applications
6th Edition
ISBN: 9780130606204
Author: Douglas C. Giancoli
Publisher: Prentice Hall
bartleby

Concept explainers

bartleby

Videos

Question
Book Icon
Chapter 20, Problem 40P
To determine

The magnitude and direction of the current in the wire.

Expert Solution & Answer
Check Mark

Answer to Problem 40P

The current in the wire is 19.4 A facing down.

Explanation of Solution

Given:

A compass needle changes its direction from 23° E of N to 55°E of N from the vertical wire, when placed 12 cm east of wire.

Earth’s magnetic field is 0.5×104 T horizontally.

Formula used:

According to the law of sines,

  FAsinθA=FBsinθB

Calculation:

Considering, both the changes in the magnetic field around the wire is in the Earth’s magnetic field. According to the diagram below, compass needle is moving towards south direction. Thus, the net magnetic field due to wire must be towards south direction.

  Physics: Principles with Applications, Chapter 20, Problem 40P

Using the geometry of the figure, angles are θ=23° , θ+ϕ=55° , and β+θ+ϕ=180° .

So, ϕ=32° , and β=125° . Now, using the law of sines, magnetic field of the wire will be

  Bwiresinϕ=BEarthsinβBwire=BEarthsinϕsinβ=μ0I2πrI = BEarthsinϕsinβ2πrμ0I = (5×105T)sin320sin12502π(0.120 m)4π×107Tm/AI =19.4 A

Since the magnetic field in the wire is facing towards the south direction. Thus, current in the wire will be towards down.

Conclusion:

Thus, the current in the wire is 19.4 A facing down.

Chapter 20 Solutions

Physics: Principles with Applications

Ch. 20 - Prob. 11QCh. 20 - Prob. 12QCh. 20 - 13. Explain why a strong magnet held near a CRT...Ch. 20 - Prob. 14QCh. 20 - Prob. 15QCh. 20 - Prob. 16QCh. 20 - Prob. 17QCh. 20 - If a moving charged particle is deflected sideways...Ch. 20 - Prob. 19QCh. 20 - Prob. 20QCh. 20 - Prob. 21QCh. 20 - Prob. 22QCh. 20 - Prob. 23QCh. 20 - Why will either pole of a magnet attract an...Ch. 20 - Prob. 25QCh. 20 - Prob. 26QCh. 20 - Prob. 27QCh. 20 - Prob. 28QCh. 20 - Prob. 29QCh. 20 - Prob. 30QCh. 20 - Prob. 31QCh. 20 - Prob. 1PCh. 20 - Prob. 2PCh. 20 - A 240-m length of wire stretches between two...Ch. 20 - Prob. 4PCh. 20 - Prob. 5PCh. 20 - Prob. 6PCh. 20 - Prob. 7PCh. 20 - Prob. 8PCh. 20 - Prob. 9PCh. 20 - Prob. 10PCh. 20 - Prob. 11PCh. 20 - Find the direction of the force on a negative...Ch. 20 - Prob. 13PCh. 20 - Prob. 14PCh. 20 - Prob. 15PCh. 20 - Prob. 16PCh. 20 - Prob. 17PCh. 20 - Prob. 18PCh. 20 - Prob. 19PCh. 20 - Prob. 20PCh. 20 - Prob. 21PCh. 20 - Prob. 22PCh. 20 - Prob. 23PCh. 20 - Prob. 24PCh. 20 - Prob. 25PCh. 20 - Prob. 26PCh. 20 - Prob. 27PCh. 20 - Prob. 28PCh. 20 - Prob. 29PCh. 20 - Prob. 30PCh. 20 - Prob. 31PCh. 20 - Prob. 32PCh. 20 - Prob. 33PCh. 20 - Prob. 34PCh. 20 - Prob. 35PCh. 20 - Prob. 36PCh. 20 - Prob. 37PCh. 20 - Prob. 38PCh. 20 - Prob. 39PCh. 20 - Prob. 40PCh. 20 - Prob. 41PCh. 20 - Prob. 42PCh. 20 - Prob. 43PCh. 20 - Prob. 44PCh. 20 - Prob. 45PCh. 20 - Prob. 46PCh. 20 - Prob. 47PCh. 20 - Prob. 48PCh. 20 - Prob. 49PCh. 20 - Prob. 50PCh. 20 - Prob. 51PCh. 20 - Prob. 52PCh. 20 - Prob. 53PCh. 20 - A circular coil 12.0 cm in diameter and containing...Ch. 20 - Prob. 55PCh. 20 - Prob. 56PCh. 20 - Prob. 57PCh. 20 - Prob. 58PCh. 20 - Prob. 59PCh. 20 - Prob. 60PCh. 20 - Prob. 61PCh. 20 - Prob. 62PCh. 20 - Prob. 63PCh. 20 - Prob. 64PCh. 20 - Prob. 65PCh. 20 - Prob. 66PCh. 20 - Prob. 67GPCh. 20 - Prob. 68GPCh. 20 - Prob. 69GPCh. 20 - Prob. 70GPCh. 20 - Prob. 71GPCh. 20 - Prob. 72GPCh. 20 - Prob. 73GPCh. 20 - Prob. 74GPCh. 20 - Prob. 75GPCh. 20 - Prob. 76GPCh. 20 - Prob. 77GPCh. 20 - Prob. 78GPCh. 20 - Prob. 79GPCh. 20 - Prob. 80GPCh. 20 - Prob. 81GPCh. 20 - Prob. 82GPCh. 20 - Prob. 83GPCh. 20 - Prob. 84GPCh. 20 - Prob. 85GPCh. 20 - Prob. 86GPCh. 20 - Prob. 87GP
Knowledge Booster
Background pattern image
Physics
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, physics and related others by exploring similar questions and additional content below.
Recommended textbooks for you
Text book image
College Physics
Physics
ISBN:9781305952300
Author:Raymond A. Serway, Chris Vuille
Publisher:Cengage Learning
Text book image
University Physics (14th Edition)
Physics
ISBN:9780133969290
Author:Hugh D. Young, Roger A. Freedman
Publisher:PEARSON
Text book image
Introduction To Quantum Mechanics
Physics
ISBN:9781107189638
Author:Griffiths, David J., Schroeter, Darrell F.
Publisher:Cambridge University Press
Text book image
Physics for Scientists and Engineers
Physics
ISBN:9781337553278
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning
Text book image
Lecture- Tutorials for Introductory Astronomy
Physics
ISBN:9780321820464
Author:Edward E. Prather, Tim P. Slater, Jeff P. Adams, Gina Brissenden
Publisher:Addison-Wesley
Text book image
College Physics: A Strategic Approach (4th Editio...
Physics
ISBN:9780134609034
Author:Randall D. Knight (Professor Emeritus), Brian Jones, Stuart Field
Publisher:PEARSON
THE BAR MAGNET; Author: 7activestudio;https://www.youtube.com/watch?v=DWQfL5IJTaQ;License: Standard YouTube License, CC-BY