WBJEE · Physics · Magnetic Effects of Current
An electron revolves around the nucleus in a circular path with angular momentum \(\overrightarrow{\mathrm{L}} . \mathrm{A}\) uniform magnetic field \(\overrightarrow{\mathrm{B}}\) is applied perpendicular to the plane of its orbit. If the electron experiences a torque \(\overrightarrow{\mathrm{T}}\), then
- A \(\overrightarrow{\mathrm{T}} \| \overrightarrow{\mathrm{L}}\)
- B \(\overrightarrow{\mathrm{T}}\) is anti-parallel to \(\overrightarrow{\mathrm{L}}\)
- C \(\overrightarrow{\mathrm{T}} \cdot \overrightarrow{\mathrm{L}}=0\)
- D Angle between \(\vec{T}\) and \(\vec{L}\) is \(45^{\circ}\)
Answer & Solution
Correct Answer
(C) \(\overrightarrow{\mathrm{T}} \cdot \overrightarrow{\mathrm{L}}=0\)
Step-by-step Solution
Detailed explanation
\(\vec{\tau}=0 \Rightarrow \vec{\tau} \cdot \vec{L}=0\)
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