Verified Solution • 2025–26 Session moderate

QPages 121-124: Q48.1: HC Verma: Concepts of Physics - Volume 2 Electric Field Potential Pages 121-124: Q48.1 Solution: A particle of mass 1 g and charge is released from rest in an…

⚠️ Common Exam Traps & Conceptual Pitfalls

Students frequently fail to convert the mass from grams to kilograms before calculating gravitational force, leading to an error of a factor of 1000. Always ensure mass is in SI units (kg) when applying $F_g = mg$ to maintain consistency with the electric force calculation.

A particle of mass 1 g and charge 2.5×10−4 C2.5 \times 10^{-4} \text{ C} is released from rest in an electric field of 1.2×104 N C−11.2 \times 10^4 \text{ N C}^{-1}. Find the electric force and the force of gravity acting on this particle. Can one of these forces be neglected in comparison with the other for approximate analysis?

Step-by-Step Verified Solution

**Answer:** Fe=30F_e = 30 N, Fg=0.01F_g = 0.01 N. Electric force dominates. **Step-BY-STEP Explanation:** Given: m=1m = 1 g = 10−310^{-3} kg, q=2.5×10−4q = 2.5 \times 10^{-4} C, E=1.2×104E = 1.2 \times 10^4 N/C.
Fe=qE=2.5×10−4×1.2×104=3 NF_e = qE = 2.5 \times 10^{-4} \times 1.2 \times 10^4 = 3 \text{ N}
Fg=mg=10−3×10=0.01 NF_g = mg = 10^{-3} \times 10 = 0.01 \text{ N}
Electric force is 300 times larger, so gravity can be neglected .

All Questions in this Chapter

QPage 119: Q1 QPage 119: Q2 QPage 119: Q3 QPage 119: Q4 QPage 119: Q5 QPage 119: Q6 QPage 119: Q7 QPage 119: Q8 QPage 119: Q9 QPage 119: Q10 QPage 119: Q11 QPage 119: Q12 QPage 119: Q13 QPage 119: Q14 QPage 120: Q1 QPage 120: Q2 QPage 120: Q3 QPage 120: Q4 QPage 120: Q5 QPage 120: Q6 QPage 120: Q7 QPage 120: Q8 QPages 119-120: Q1 QPages 119-120: Q2 QPages 119-120: Q3 QPages 119-120: Q4 QPages 119-120: Q5 QPages 119-120: Q6 QPages 119-120: Q7 QPages 119-120: Q8 QPages 119-120: Q9 QPages 121-124: Q1 QPages 121-124: Q2 QPages 121-124: Q3 QPages 121-124: Q4 QPages 121-124: Q5 QPages 121-124: Q6 QPages 121-124: Q7 QPages 121-124: Q8 QPages 121-124: Q9 QPages 121-124: Q10 QPages 121-124: Q11 QPages 121-124: Q12 QPages 121-124: Q13 QPages 121-124: Q14 QPages 121-124: Q15.1 QPages 121-124: Q15.2 QPages 121-124: Q16 QPages 121-124: Q17 QPages 121-124: Q18 QPages 121-124: Q19 QPages 121-124: Q20 QPages 121-124: Q21 QPages 121-124: Q22 QPages 121-124: Q23 QPages 121-124: Q24 QPages 121-124: Q25 QPages 121-124: Q26 QPages 121-124: Q27 QPages 121-124: Q28 QPages 121-124: Q29 QPages 121-124: Q30 QPages 121-124: Q31 QPages 121-124: Q32.1 QPages 121-124: Q32.2 QPages 121-124: Q32.3 QPages 121-124: Q33 QPages 121-124: Q34 QPages 121-124: Q35 QPages 121-124: Q36 QPages 121-124: Q37 QPages 121-124: Q38 QPages 121-124: Q39 QPages 121-124: Q40 QPages 121-124: Q41 QPages 121-124: Q42 QPages 121-124: Q43 QPages 121-124: Q44 QPages 121-124: Q45 QPages 121-124: Q46 QPages 121-124: Q47 QPages 121-124: Q48.1 QPages 121-124: Q48.2 QPages 121-124: Q48.3 QPages 121-124: Q48.4 QPages 121-124: Q49 QPages 121-124: Q50 QPages 121-124: Q51 QPages 121-124: Q52 QPages 121-124: Q53 QPages 121-124: Q54 QPages 121-124: Q55 QPages 121-124: Q56 QPages 121-124: Q57 QPages 121-124: Q58 QPages 121-124: Q59 QPages 121-124: Q60 QPages 121-124: Q61 QPages 121-124: Q62 QPages 121-124: Q63 QPages 121-124: Q64 QPages 121-124: Q65 QPages 121-124: Q66 QPages 121-124: Q67 QPages 121-124: Q68 QPages 121-124: Q69 QPages 121-124: Q70 QPages 121-124: Q71.1 QPages 121-124: Q71.2 QPages 121-124: Q71.3 QPages 121-124: Q72 QPages 121-124: Q73 QPages 121-124: Q74 QPages 121-124: Q75

Related Learning Resources & Exam Preparation

Chapter Practice Bank
Practice all topic-wise questions from Electric Field Potential
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