Q49.A tightly wound long solenoid carries a current of 1.5 A . An electron is executing uniform circular motion inside the solenoid with a time period of 75 ns . The number of turns per metre in the solenoid is … … -. [Take mass of electron me = 9 × 10−31 kg, charge of electron |qe| = 1.6 × 10−19C, μ0 = 4π × 10−7 N , 1 ns = 10−9 A2 s]
What This Question Tests
This question combines the concept of the magnetic field generated by a solenoid with the circular motion of an electron under the influence of this magnetic field to determine the number of turns per unit length.
Concepts Tested
Formulas Used
B = μ_0 n I
F = qvB
F = mv^2/r
T = 2πm / (qB)
📚 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.
4.6 — A 3.0 Cm Wire Carrying A Current Of 10 A Is Placed Inside A Solenoid
Physics Class 11 · Chapter 4
4.6 A 3.0 cm wire carrying a current of 10 A is placed inside a solenoid perpendicular to its axis. The magnetic field inside the solenoid is given to be 0.27 T. What is the magnetic force on the wire?
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)
📋 Question Details
- Chapter
- Magnetic Effects of Current
- Topic
- Motion of charge in uniform magnetic field
- Year
- 2025
- Shift
- 24 Jan Shift 2
- Q Number
- Q49
- Type
- Multi concept
- NCERT Ref
- Class 12 Physics Ch 4: Magnetic Effects of Current
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