Question

What accelerating potential is needed to produce electrons of wavelength 5.20 nm? V- 10.5563 Previous Answers Reguest Answer Submit Incorrect; Try Again; 5 attempts remaining ▼ Part B What would be the energy of photons having the same wavelength as these electrons? eV Submit Request Answer

Answer 1

Answer:

(a) 55.67 mV

(b) 238 eV

Explanation:

(a) Let the accelerating voltage is v.

The formula for the accelerating voltage and the potential difference is given by

$\lambda = \frac{12.27\times 10^{-10}}{\sqrt{V}}$

Here, λ = 5.20 nm = 5.20 x 10^-9 m

$5.2\times 10^{-9} = \frac{12.27\times 10^{-10}}{\sqrt{V}}$

V = 0.0556 V = 55.67 mV

(b) Let the energy is E.

The formula for the energy is given by

$E = \frac{hc}{\lambda }$

E = (6.6 x 10^-34 x 3 x 10^8) / (5.2 x 10^-9) = 3.8 x 10^-17 J

E = (3.8 x 10^-17) / (1.6 x 10^-19) = 238 eV