A wire of length 314 cm carrying current of 14 A is bent to form a circle. The magnetic moment of the coil is _______ A–m2. [Given \(\pi = 3.14\)]
Correct Answer: 11
Solution and Explanation
\(R = \frac{I}{2\pi}\)
\(\frac{314}{2 \times 3.14}\)
\(=50 cm\)
The magnetic moment of the coil,
\(\mu = \pi R^2 i\)
\(14 \times 3.14 \times (0.5)^2\)
\(= 11\) A-m2
So, the answer is 11.
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Concepts Used:
Electromagnetic Induction
Electromagnetic Induction is a current produced by the voltage production due to a changing magnetic field. This happens in one of the two conditions:-
- When we place the conductor in a changing magnetic field.
- When the conductor constantly moves in a stationary field.
Formula:
The electromagnetic induction is mathematically represented as:-
e=N × d∅.dt
Where
- e = induced voltage
- N = number of turns in the coil
- Φ = Magnetic flux (This is the amount of magnetic field present on the surface)
- t = time
Applications of Electromagnetic Induction
- Electromagnetic induction in AC generator
- Electrical Transformers
- Magnetic Flow Meter