Verified Solution • 2025–26 Session moderate

QPages 277-278: Q2: HC Verma: Concepts of Physics - Volume 2 Permanent Magnets Pages 277-278: Q2 Solution: Two long bare magnets are placed with their axes coinciding in…

⚠️ Common Exam Traps & Conceptual Pitfalls

Students frequently forget to convert the distance from centimeters to meters before applying Coulomb's law for magnetism, leading to a $10^4$ error in the force calculation. Always ensure $r$ is in SI units (meters) when using $rac{mu_0}{4pi} = 10^{-7} ext{ N/A}^2$.

Two long bare magnets are placed with their axes coinciding in such a way that the north pole of the first magnet is 2.0 cm from the south pole of the second. If both the magnets have a pole strength of 10 Am, find the force exerted by one magnet of the other.

Step-by-Step Verified Solution

**Answer:**

F = 2.5 \times 10^{-2} \text{ N}

. **Step-by-Step Explanation:** Given:

m_1 = m_2 = 10 \text{ Am}

,

r = 2 \text{ cm} = 0.02 \text{ m}

.

F = \frac{\mu_0}{4\pi} \frac{m_1 m_2}{r^2} = 10^{-7} \times \frac{100}{4 \times 10^{-4}} = 2.5 \times 10^{-2} \text{ N}

[citation:17].

All Questions in this Chapter

QPage 276: Q1 QPage 276: Q2 QPage 276: Q3 QPage 276: Q4 QPage 276: Q5 QPage 276: Q6 QPage 276: Q7 QPage 276: Q8 QPage 276: Q9 QPage 276: Q10 QPage 276: Q11 QPage 276: Q12 QPage 276: Q13 QPage 277: Q1 QPage 277: Q2 QPage 277: Q3 QPage 277: Q4 QPage 277: Q5 QPages 275-276: Q1 QPages 275-276: Q2 QPages 275-276: Q3 QPages 275-276: Q4 QPages 275-276: Q5 QPages 275-276: Q6 QPages 275-276: Q7 QPages 275-276: Q8 QPages 275-276: Q9 QPages 275-276: Q10 QPages 275-276: Q11 QPages 277-278: Q1 QPages 277-278: Q2 QPages 277-278: Q3 QPages 277-278: Q4 QPages 277-278: Q5 QPages 277-278: Q6 QPages 277-278: Q7 QPages 277-278: Q8 QPages 277-278: Q9 QPages 277-278: Q10 QPages 277-278: Q11 QPages 277-278: Q12 QPages 277-278: Q13 QPages 277-278: Q14 QPages 277-278: Q15 QPages 277-278: Q16 QPages 277-278: Q17 QPages 277-278: Q18 QPages 277-278: Q19 QPages 277-278: Q20 QPages 277-278: Q21 QPages 277-278: Q22 QPages 277-278: Q23 QPages 277-278: Q24 QPages 277-278: Q25

Related Learning Resources & Exam Preparation

Chapter Practice Bank

Practice all topic-wise questions from Permanent Magnets

Reference Textbook Solutions

Explore complete chapter exercises for HC Verma: Concepts of Physics - Volume 2

Competitive PYQ Question Bank

Browse year-wise authentic previous years' questions with solutions

Authentic CBT Mock Tests

Simulate official exam environment with live timer and percentile scoring