Question:easy
The magnetic field at a distance 'r' from a long straight wire carrying current I is 0.4 tesla. The magnetic field at a distance 2r will be
The magnetic field at a distance 'r' from a long straight wire carrying current I is 0.4 tesla. The magnetic field at a distance 2r will be
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The period is 2 pi m over q B, which has no velocity in it.
Updated On: Oct 1, 2026
- \(0\cdot 1\) tesla
- \(0\cdot 2\) tesla
- \(0\cdot 8\) tesla
- \(1\cdot 6\) tesla
Show Solution
The Correct Option is B
Solution and Explanation
Step 1: Frequency form:
Cyclotron frequency $f = \frac{qB}{2\pi m}$.
Step 2: Observation:
This contains q, B and m only. A faster particle moves on a larger circle, but needs the same time for one turn. So (B).
Final Answer:
Velocity. \[ \boxed{\text{(B)}} \]
Cyclotron frequency $f = \frac{qB}{2\pi m}$.
Step 2: Observation:
This contains q, B and m only. A faster particle moves on a larger circle, but needs the same time for one turn. So (B).
Final Answer:
Velocity. \[ \boxed{\text{(B)}} \]
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