Q15.A charge particle moves along circular path in a uniform magnetic field in a cyclotron. The kinetic energy of the charge particle increases to 4 times its initial value. What will be the ratio of new radius to the original radius of circular path of the charge particle? (1) 1 : 1 (2) 1 : 2 (3) 2 : 1 (4) 1 : 4
What This Question Tests
This question tests the relationship between the radius of the circular path of a charged particle in a magnetic field and its kinetic energy.
Concepts Tested
Formulas Used
r = mv/(qB)
KE = p²/(2m) = (mv)²/(2m)
📚 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 magnetic field
- Year
- 2022
- Shift
- 29 Jun Shift 1
- Q Number
- Q15
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 4: Moving Charges and Magnetism
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