WBJEE · Physics · Rotational Motion
An electron of charge \(e\) and mass \(m\) is moving in a circular of radius \(r\) with a uniform angular speed \(\omega .\) Then which of the following statements are correct?
- A The equivalent current flowing in the circular path is proportional to \(r^{2}\)
- B The magnetic moment due to circular current loop is independent of m
- C The magnetic moment due to circular current loop equal to \(2 e / m\) times the angular momentum of the electron,
- D The angular momentum of the particle is proportional to the areal velocity of electron.
Answer & Solution
Correct Answer
(D) The angular momentum of the particle is proportional to the areal velocity of electron.
Step-by-step Solution
Detailed explanation
Magnetic moment, \(m=IA\) \(=\frac{e v}{2 \pi f} \times \pi r^{2}=\frac{e v r}{2}\) Angular momentum \(=2 m \frac{d A}{d t}\)
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