Warning: foreach() argument must be of type array|object, bool given in /var/www/html/web/app/themes/studypress-core-theme/template-parts/header/mobile-offcanvas.php on line 20

A sheet of copper is placed between the poles of an electromagnet with the magnetic field perpendicular to the sheet. When the sheet is pulled out, a considerable force is required, and the force required increases with speed. Explain. Is a force required also when the sheet is inserted between the poles? Explain.

Short Answer

Expert verified

Yes, a force is also required when the sheet is inserted between the poles.

Step by step solution

01

Concept 

Lens Law

The direction of any magnetic induction effect is such as to oppose the cause of the effect.

Faraday Law of EMF

Faraday Law of EMF states that the induced emf in a loop equals the negative of the time rate of change of magnetic flux through the loop.

Mathematically it can be given by

e=-dt=BdAdt

Where, eis the EMF,ϕ is the magnetic flux, B is the applied magnetic field and A is the surface area.

02

Explanation

On pulling out the sheet from the magnetic field there is a decrease in magnetic flux occurs (due to a decrease in exposed area in the magnetic field ) which results in the production of induced current (due to production of induced EMF) in such a direction that opposes the decrease in magnetic flux.

Therefore, a considerable force is required to pull out the sheet from the magnetic field.

If there is an increase in the speed of pulling out the sheet from the magnetic field then the resulting induced current will also be larger.

Hence, more force is required with an increase in the speed of pulling out the sheet.

Similarly, on inserting the copper sheet there is an increase in magnetic flux which results in an induced current that flows in such a way to oppose magnetic flux.

Hence, a considerable force is required to insert the metal between the poles. Therefore, considerable force is required to insert the copper sheet between poles.

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 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

Current passes through a solution of sodium chloride. In

1.00s,2.68×1016Na+ions arrive at the negative electrode and3.92×1016CI-

ions arrive at the positive electrode. (a) What is the current passing between

the electrodes? (b) What is the direction of the current?

(See Discussion Question Q25.14.) Will a light bulb glow more brightly when it is connected to a battery as shown in Fig. Q25.16a, in which an ideal ammeter is placed in the circuit, or when it is connected as shown in Fig. 25.16b, in which an ideal voltmeter V is placed in the circuit? Explain your reasoning.

A heart defibrillator is used to enable the heart to start beating if it has stopped. This is done by passing a large current of12Athrough the body at25Vfor a very short time, usually3.0msabout . (a) What power does the defibrillator deliver to the body, and (b) how much energy is transferred ?

Questions: When a thunderstorm is approaching, sailors at sea sometimes observe a phenomenon called “St. Elmo’s fire,” a bluish flickering light at the tips of masts. What causes this? Why does it occur at the tips of masts? Why is the effect most pronounced when the masts are wet? (Hint: Seawater is a good conductor of electricity.)

An alpha particle (a He nucleus containing two protons and two neutrons and having a mass of 6.64×10-7kg) travelling horizontally at 35.6km/senter a uniform, vertical,1.80-T magnetic field.(a) What is the diameter of the path followed by this alpha particle? (b) what effect does the magnetic field have on the speed of the particle? (c) What are the magnitude and direction of the acceleration of the alpha particle while it is in the magnetic field? (d) explain why the speed of the particle does not change even though an unbalanced external force acts on it.

See all solutions

Recommended explanations on Physics Textbooks

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