/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 8 A bar magnet, of magnetic moment... [FREE SOLUTION] | 91影视

91影视

Log out

Learning Materials

Features

Discover

Chapter 16: Problem 8

A bar magnet, of magnetic moment \(M\), is placed in a magnetic field of induction \(B\). The torque exerted on it is (A) \(\vec{M} \cdot \vec{B}\) (B) \(\vec{B} \times \vec{M}\) (C) \(\vec{M} \times \vec{B}\) (D) \(-\vec{B} \cdot \vec{M}\)

Short Answer

Expert verified
The correct answer to the problem is (C) \(\vec{M} \times \vec{B}\). The torque exerted on the bar magnet is accurately represented by this expression.

Step by step solution

01

Understanding Torque

When a magnetic moment \(M\) is placed in a magnetic field of induction \(B\), it experiences a torque. Torque \(\tau\) of a magnet is the turning force that causes the magnet to rotate until it gets aligned with the magnetic field. The expression for this torque is given by \(\tau = \vec{M} \times \vec{B}\).
02

Evaluation of the given choices

Now, evaluate each option and compare them with the right expression for torque. (A) \(\vec{M} \cdot \vec{B}\) is incorrect as the torque is not a scalar product of \(\vec{M}\) and \(\vec{B}\). (B) \(\vec{B} \times \vec{M}\) is incorrect because the torque is not calculated by taking the cross product of \(\vec{B}\) and \(\vec{M}\). (D) \(-\vec{B} \cdot \vec{M}\) is incorrect as it represents a negative scalar product, not a vector cross product.
03

Choosing the correct option

Comparison of the torque's actual expression with the provided options shows that option (C) \(\vec{M} \times \vec{B}\) is correct. This option correctly represents the cross product of \(\vec{M}\) and \(\vec{B}\), indicating that the torque exerted on the magnet is a vector quantity.

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.

Over 30 million students worldwide already upgrade their learning with 91影视!

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

A varying magnetic flux linking a coil is given by \(\phi=3 t^{2}\). The magnitude of induced EMF in the loop at \(t=3 \mathrm{~s}\) is (A) \(3 \mathrm{~V}\) (B) \(9 \mathrm{~V}\) (C) \(18 \mathrm{~V}\) (D) \(27 \mathrm{~V}\)

A flat coil carrying a current has a magnetic moment \(\vec{\mu}\). It is placed in a magnetic field \(\vec{B}\). The torque on the coil is \(\vec{\tau}\), then (A) \(\vec{\tau}=\vec{\mu} \cdot \vec{B}\) (B) \(\vec{\tau}=\vec{B} \times \vec{\mu}\) (C) \(|\vec{\tau}|=\vec{\mu} \cdot \vec{B}\) (D) \(\vec{\tau}\) is perpendicular to both \(\vec{\mu}\) and \(\vec{B}\).

An iron rod of cross-sectional area 4 sq \(\mathrm{cm}\) is placed with its length parallel to a magnetic field of intensity \(1600 \mathrm{amp} / \mathrm{m}\). The flux through the rod is \(4 \times 10^{-4}\) weber. The permeability of the material of the rod is (In weber/amp-m). (A) \(0.625\) (B) \(6.25\) (C) \(0.625 \times 10^{-3}\) (D) None of these

Two coils of self-inductance \(4 \mathrm{H}\) and \(16 \mathrm{H}\) are wound on the same iron core. The coefficient of mutual inductance for them will be (A) \(8 \mathrm{H}\) (B) \(10 \mathrm{H}\) (C) \(20 \mathrm{H}\) (D) \(64 \mathrm{H}\)

A coil of inductance \(1 H\) and resistance \(10 \Omega\) is connected to a resistance-less battery of EMF \(50 \mathrm{~V}\) at time \(t=0 .\) The ratio of rate at which magnetic energy is stored in the coil to the rate at which energy is supplied by the battery at \(t=0.1 \mathrm{~s} .\) is \(x \times 10^{-2}\). Find the value of \(x\). (Given \(\left.\frac{1}{e}=0.37\right)\)
See all solutions

Recommended explanations on Physics Textbooks

Electricity and Magnetism

Read Explanation

Solid State Physics

Read Explanation

Magnetism and Electromagnetic Induction

Read Explanation

Torque and Rotational Motion

Read Explanation

Radiation

Read Explanation

Electric Charge Field and Potential

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.