12. ATOMS (HM)
191472
\(1.65 Å\) तरंगदैध्र्य के \(X-\) किरण फोटॉन की ऊर्जा.......\(keV\) है\((h = 6.6 \times {10^{ - 34}}J{\rm{ - }}sec,\,\,c = 3 \times {10^8}m{s^{ - 1}}\), \(1eV = 1.6 \times {10^{ - 19}}J)\)
1 \(3.5 \)
2 \(5.5\)
3 \(7.5\)
4 \(9.5\)
Explanation:
\(E(eV) = \frac{{12375}}{{1.65}} = 7500eV = 7.5\,\,keV\)