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JEE Mains · Physics · STD 12 - 11. Dual nature of radiation and matter
In an electron microscope, the resolution that can be achieved is of the order of the wavelength of electrons used. To resolve a width of \(7.5 \times 10^{-12}\, m\), the minimum electron energy required is close to .............. \(keV\)
- A \(500\)
- B \(100\)
- C \(1\)
- D \(25\)
Answer & Solution
Correct Answer
(D) \(25\)
Step-by-step Solution
Detailed explanation
\(\mathrm{k}=\frac{\mathrm{P}^{2}}{2 \mathrm{m}}=\frac{\mathrm{h}^{2}}{2 \mathrm{m} \lambda^{2}}\) \( = \frac{{{{\left( {6.62 \times {{10}^{ - 34}}} \right)}^2}}}{{2 \times 9.1 \times {{10}^{ - 31}} \times {{\left( {7.5 \times {{10}^{ - 12}}} \right)}^2}}}\)…
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