Einstein’s Photoelectric Equation MCQs
Einstein’s Photoelectric Equation MCQs
Class: CBSE Class 12
Subject: Physics
Section: Dual Nature of Radiation & Matter
Topic: Einstein’s Photoelectric Equation
Based on: CBSE Board Examination Pattern (NCERT)
Instructions: These Multiple Choice Questions (MCQs) are designed strictly as per the NCERT syllabus, making them ideal for CBSE Class 12 Board Examination preparation.
1. Einstein’s photoelectric equation is:
Answer: A
Photon energy is used to overcome work function and give KE to electron.
Photon energy is used to overcome work function and give KE to electron.
2. Work function (φ) is:
Answer: B
It is the minimum energy required to remove an electron.
It is the minimum energy required to remove an electron.
3. If ν = ν₀, KEmax is:
Answer: B
All energy is used to overcome work function.
All energy is used to overcome work function.
4. Stopping potential measures:
Answer: B
eV₀ = KEmax.
eV₀ = KEmax.
5. Increasing frequency increases:
Answer: B
KEmax = hν − φ.
KEmax = hν − φ.
6. If φ = 2 eV and photon energy = 5 eV, KEmax =
Answer: B
KE = 5 − 2 = 3 eV.
KE = 5 − 2 = 3 eV.
7. If stopping potential = 4 V, KEmax =
Answer: A
KE = eV₀ = 4 eV.
KE = eV₀ = 4 eV.
8. Threshold frequency depends on:
Answer: B
Material property.
Material property.
9. If ν increases, stopping potential:
Answer: A
Higher KE requires higher stopping voltage.
Higher KE requires higher stopping voltage.
10. Photon energy formula:
Answer: A
Planck’s quantum relation.
Planck’s quantum relation.
11. Photoelectric emission proves light is:
Answer: B
Photons transfer discrete energy.
Photons transfer discrete energy.
12. No emission if:
Answer: A
Frequency must exceed threshold.
Frequency must exceed threshold.
13. Photocurrent depends on:
Answer: A
More photons → more electrons.
More photons → more electrons.
14. KEmax depends on:
Answer: B
Given by equation.
Given by equation.
15. Graph of KE vs ν is:
Answer: A
Linear relation.
Linear relation.
16. Slope of KE vs ν graph:
Answer: A
Slope equals Planck constant.
Slope equals Planck constant.
17. Intercept on ν-axis gives:
Answer: B
Threshold frequency.
Threshold frequency.
18. Larger φ means:
Answer: B
More energy required.
More energy required.
19. Device based on equation:
Answer: A
Operates on photoelectric principle.
Operates on photoelectric principle.
20. Einstein equation supports:
Answer: A
Energy quantisation concept.
Energy quantisation concept.
