A closely wound solenoid of 2000 turns and area of cross-section 1.5 x 10⁻⁴ m² carries

⇦

⇨

A closely wound solenoid of 2000 turns and area of cross-section 1.5 x 10⁻⁴ m² carries a current of 2.0 A. It suspended through its centre and perpendicular to its length, allowing it to turn in a horizontal plane in a uniform magnetic field 5 x 10⁻² tesla making an angle of 30with the axis of the solenoid. The torque on the solenoid will be:

Options

(a) 3 x 10⁻² N-m
(b) 3 x 10⁻³ N-m
(c) 1.5 x 10⁻³ N-m
(d) 1.5 x 10⁻² N-m

Correct Answer:

1.5 x 10⁻² N-m

Explanation:

Torque on the solenoid is given by ? = MB sin θ
where θ is the angle between the magnetic field and the axis of solenoid. M = niA
? = niA B sin 30⁰
= 2000 x 2 x 1.5 x 10⁻⁴ x 5 x 10⁻² x 1/2
= 1.5 x 10⁻² N – m

Related Questions:

1. Perfectly black body radiates the energy 18 J/s at 300K. Another ordinary body of e=0.8
2. In a LCR series circuit, the potential difference between the terminals of the inductor
3. A boat of anchor is rocked by waves whose crests are 100 m apart and velocity
4. Six molecules have speeds 2 units, 5 units, 3 units, 6 units, 3 units and 5 units
5. Two parallel long wires carry currents i₁ and i₂ with i₁ > i₂ .

Topics: Magnetic Effects of Current and Magnetism (167)
Subject: Physics (2479)

---

Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score

18000+ students are using NEETLab to improve their score. What about you?

Solve Previous Year MCQs, Mock Tests, Topicwise Practice Tests, Identify Weak Topics, Formula Flash cards and much more is available in NEETLab Android App to improve your NEET score.

---

Share this page with your friends