WBJEE · Physics · Magnetic Effects of Current
A charged particle of charge \(q\) and mass \(m\) is placed at a distance \(2 R\) from the centre of a vertical cylindrical region of radius \(R\) where magnetic field varies as \(\vec{B}=\left(4 t^2-2 t+6\right) \hat{k}\) where \(t\) is time. Then which of the following statement(s) is/are true?
- A Induced electric field lines form closed loops
- B Electric field varies linearly with \(r\) if \(r < R\), where \(r\) is the radial distance from the centerline of the cylinder
- C The charged particle will move in clockwise direction when viewed from top
- D Acceleration of the charged particle is \(\frac{7 q}{2 m}\) when \(t=2 \mathrm{sec}\)
Answer & Solution
Correct Answer
(B) Electric field varies linearly with \(r\) if \(r < R\), where \(r\) is the radial distance from the centerline of the cylinder
Step-by-step Solution
Detailed explanation
Hint : \(r R\)…
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