Q19.A particle having the same charge as of electron moves in a circular path of radius 0.5 cm under the influence of a magnetic field of 0.5 T. If an electric field of 100 V/m makes it to move in a straight path, then the mass of the particle is (Given charge of electron = 1.6 × 10−19C ) (1) 9.1 × 10−31 kg (2) 1.6 × 10−27 kg (3) 2.0 × 10−24 kg (4) 1.6 × 10−19 kg
What This Question Tests
This question combines the principles of force balance in combined electric and magnetic fields (velocity selector) to determine the particle's velocity, and then uses the magnetic force as centripetal force for circular motion to find the particle's mass.
Concepts Tested
Formulas Used
F_E = qE
F_B = qvB
qvB = mv²/r
📚 NCERT Sections This Tests
4.11 — In A Chamber, A Uniform Magnetic Field Of 6.5 G (1 G = 10–4 T) Is
Physics Class 11 · Chapter 4
4.11 In a chamber, a uniform magnetic field of 6.5 G (1 G = 10–4 T) is maintained. An electron is shot into the field with a speed of 4.8 × 106 m s–1 normal to the field. Explain why the path of the electron is a circle. Determine the radius of the circular orbit. (e = 1.5 × 10–19 C, me = 9.1×10–31 kg)
4.4 — A Horizontal Overhead Power Line Carries A Current Of 90 A In East To
Physics Class 11 · Chapter 4
4.4 A horizontal overhead power line carries a current of 90 A in east to west direction. What is the magnitude and direction of the magnetic field due to the current 1.5 m below the line?
4.5 — What Is The Magnitude Of Magnetic Force Per Unit Length On A Wire
Physics Class 11 · Chapter 4
4.5 What is the magnitude of magnetic force per unit length on a wire carrying a current of 8 A and making an angle of 30º with the direction of a uniform magnetic field of 0.15 T?
📋 Question Details
- Chapter
- Magnetic Effects of Current
- Topic
- Motion of charged particle in E and B fields
- Year
- 2019
- Shift
- 09 Jan Shift 2
- Q Number
- Q19
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 4: Moving Charges and Magnetism
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