Question

The energy levels in an atom A, B, and C are in increasing order E_A< E_B<E_C . The x-rays emitted in transitions

C ®B, B ®A and C ® A, have wavelengths l₁, l₂ and l₃ then which of the following relation is true –

• A. l₃ = l₁ + l₂
• B. l₃ =$\frac{\lambda_{1}\lambda_{2}}{\lambda_{1} + \lambda_{2}}$
• C. l₁ + l₂ + l₃ = 0
• D. None

Answer 1

Answer: (B)

l₃ =$\frac{\lambda_{1}\lambda_{2}}{\lambda_{1} + \lambda_{2}}$

Answer 2

DE_C®A= DE_C®B + DE_B®A

$\frac { \mathrm { hc } } { \lambda _ { 3 } }$= $\frac { \mathrm { hc } } { \lambda _ { 1 } }$ +

or l₃ = $\frac { \lambda _ { 1 } \lambda _ { 2 } } { \lambda _ { 1 } + \lambda _ { 2 } }$