Photo AI
Electromagnetic radiation of frequency 9.0 x 10^{14} Hz is incident on a clean, negatively charged metal surface - Scottish Highers Physics - Question 14 - 2023
Question 14
Electromagnetic radiation of frequency 9.0 x 10^{14} Hz is incident on a clean, negatively charged metal surface. The work function of the metal is 6.1 x 10^{-19} J.... show full transcript
Worked Solution & Example Answer:Electromagnetic radiation of frequency 9.0 x 10^{14} Hz is incident on a clean, negatively charged metal surface - Scottish Highers Physics - Question 14 - 2023
Step 1
C the frequency of the incident radiation is less than the threshold frequency of this metal
Answer
To determine whether photoelectric emission occurs, we first need to calculate the energy of the incident photons using the formula:
u$$ where: - $E$ is the energy of the photons, - $h$ is Planck's constant ($6.626 \times 10^{-34} \, \text{J s}$), - $\nu$ is the frequency of the radiation. Substituting in the values: $$E = 6.626 \times 10^{-34} \, \text{J s} \times 9.0 \times 10^{14} \, \text{Hz}$$ Calculating this gives: $$E \approx 5.9654 \times 10^{-19} \, \text{J}$$ Next, we compare this energy to the work function of the metal, which is given as $6.1 \times 10^{-19} \, \text{J}$. Since the energy of the incident photons ($5.9654 \times 10^{-19} \, \text{J}$) is less than the work function ($6.1 \times 10^{-19} \, \text{J}$), no photoelectric effect can occur. Thus, the explanation is that the frequency of the incident radiation is indeed less than the threshold frequency required for photoemission.