Force between two identical bar magnets whose centers are I meter apart is \(4.8 \mathrm{~N}\), when their axes are in the same line. If separation is increased to \(2 r\), the force between them is reduced to (a) \(2.4 \mathrm{~N}\) (b) \(1.2 \mathrm{~N}\) (c) \(0.6 \mathrm{~N}\) (d) \(0.3 \mathrm{~N}\)

Short Answer

Expert verified
The short answer is: The force between the two identical bar magnets when their separation is increased to 2 meters is \(1.2 \mathrm{~N}\).

Step by step solution

01

Identify the formula for the force between two bar magnets

The force between two identical bar magnets can be represented as follows: \(F \propto \frac{m_1 m_2}{d^2}\) Where F is the force between the magnets, m_1 and m_2 are their magnetic moments, and d is the distance between them. Since the magnets are identical, we can simplify the formula as: \(F \propto \frac{m^2}{d^2}\) Here we can introduce a constant k to convert the proportionality to an equation: \(F = k\frac{m^2}{d^2}\)
02

Calculate the constant k using the initial conditions

We know that when the distance between the magnets is 1 meter, the force between them is 4.8 N. We will use this information to find the constant k: \(4.8 = k\frac{m^2}{(1)^2}\) Solving for k, \(k = 4.8m^2\)
03

Calculate the new force when the distance is increased to 2 meters

Now, we will use the equation to find the force when the distance between the magnets is increased to 2 meters: \(F_{new} = k\frac{m^2}{(2)^2}\) Substitute the value of k from Step 2: \(F_{new} = (4.8m^2)\frac{m^2}{(2)^2}\) Solve for \(F_{new}\): \(F_{new} = \frac{4.8m^4}{4}\) Simplify the expression: \(F_{new} = 1.2m^4\) In this situation, the new force F is proportional to \(1.2m^4\). Since the proportionality constant is the same as before, the new force can be represented as: \(F_{new} = 1.2(4.8)\) \(F_{new} = 1.2 \mathrm{~N}\)
04

Choose the correct answer

From the options provided: (a) 2.4 N (b) 1.2 N (c) 0.6 N (d) 0.3 N The correct answer is (b) 1.2 N, as calculated in the previous step.

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

See all solutions

Recommended explanations on English 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