Q21.A thin ring of 10 cm radius carries a uniformly distributed charge. The ring rotates at a constant angular speed of 40π rads-1 about its axis, perpendicular to its plane. Is the magnetic field its centre is 3.8 × 10-9T , then the charge carried by the ring is close to μ0 = 4π × 10-7N / A2 . (1) 4 × 10-5 C (2) 3 × 10-5 C (3) 2 × 10-6 C (4) 7 × 10-6 C
What This Question Tests
This problem involves calculating the current produced by a uniformly charged ring rotating and then using this current to find the magnetic field at its center.
Concepts Tested
Formulas Used
I = qf = qω/(2π)
B = μ₀I/(2R)
📚 NCERT Sections This Tests
4.8 — A Closely Wound Solenoid 80 Cm Long Has 5 Layers Of Windings Of 400
Physics Class 11 · Chapter 4
4.8 A closely wound solenoid 80 cm long has 5 layers of windings of 400 turns each. The diameter of the solenoid is 1.8 cm. If the current carried is 8.0 A, estimate the magnitude of B inside the solenoid near its centre.
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)
4.9 — A Square Coil Of Side 10 Cm Consists Of 20 Turns And Carries A Current
Physics Class 11 · Chapter 4
4.9 A square coil of side 10 cm consists of 20 turns and carries a current of 12 A. The coil is suspended vertically and the normal to the plane of the coil makes an angle of 30º with the direction of a uniform horizontal magnetic field of magnitude 0.80 T. What is the magnitude of torque experienced by the coil?
📋 Question Details
- Chapter
- Magnetic Effects of Current
- Topic
- Magnetic Field due to a Rotating Charged Ring
- Year
- 2019
- Shift
- 12 Apr Shift 1
- Q Number
- Q21
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 4: Magnetic Effects of Current
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