JEE Mains · Physics · STD 12 - 12. atoms
The radiation corresponding to \(3 \rightarrow 2\) transition ofhydrogen atom falls on a metal surface to produce photoelectrons. These electrons are made to enter a magnetic field of \(3 \times 10^{-4}\) \(T\) If the radius of the largest circular path followed by these electrons is \(10.0\ mm\), the work function of the metal is close to......\( eV\)
- A \(1.1\)
- B \(0.8\)
- C \(1.6 \)
- D \(1.8\)
Answer & Solution
Correct Answer
(A) \(1.1\)
Step-by-step Solution
Detailed explanation
Radius of circular path followed by electron is given by, \(r=\frac{m v}{q B}=\frac{\sqrt{2 m e V}}{e B}=\frac{1}{B} \sqrt{\frac{2 m}{e} V}\) \(\Rightarrow \quad V=\frac{B^{2} r^{2} e}{2 m}=0.8 \mathrm{V}\) For transition between \(3\) to \(2\) .…
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