Electromagnetism
Current Electricity
MCQ (Single Correct Answer)
Moving Charges and Magnetism
MCQ (Single Correct Answer)
Magnetism and Matter
MCQ (Single Correct Answer)
Electromagnetic Induction
MCQ (Single Correct Answer)
Alternating Current
MCQ (Single Correct Answer)
Electromagnetic Waves
MCQ (Single Correct Answer)
Modern Physics
Dual Nature of Radiation
MCQ (Single Correct Answer)
Semiconductor Devices and Logic Gates
MCQ (Single Correct Answer)
Communication Systems
MCQ (Single Correct Answer)
1
COMEDK 2023 Morning Shift
MCQ (Single Correct Answer)
+1
-0

When a certain metal surface is illuminated with light of frequency $$\nu$$, the stopping potential for photoelectric current is $$V_0$$. When the same surface is illuminated by light of frequency $$\frac{\nu}{2}$$, the stopping potential is $$\frac{V_0}{4}$$. The threshold frequency for photoelectric emission is

A
$$\frac{\nu}{6}$$
B
$$\frac{\nu}{3}$$
C
$$\frac{2\nu}{3}$$
D
$$\frac{4\nu}{3}$$
2
COMEDK 2023 Morning Shift
MCQ (Single Correct Answer)
+1
-0

Let $$K_1$$ be the maximum kinetic energy of photoelectrons emitted by light of wavelength $$\lambda_1$$ and $$K_2$$ corresponding to wavelength $$\lambda_2$$. If $$\lambda_1=2 \lambda_2$$, then

A
$$2 K_1=K_2$$
B
$$K_1=2 K_2$$
C
$$K_1 < K_2 / 2$$
D
$$K_1>2 K_2$$
3
COMEDK 2023 Evening Shift
MCQ (Single Correct Answer)
+1
-0

In the photoelectric experiment, the frequency of the incident radiation is doubled. What will be its effect on the photoelectric current?

A
Photoelectric current will be halved
B
Photoelectric current will be doubled
C
Photoelectric current will not change.
D
Photoelectric current will become zero
4
COMEDK 2022
MCQ (Single Correct Answer)
+1
-0

Ultraviolet light of wavelength 99 mm falls on a metal plate of work function 1.0 eV. If the mass of the electron is 9.1 $$\times$$ 10$$^{-31}$$ kg, the wavelength of the fastest photoelectron emitted is

A
0.63 nm
B
0.66 nm
C
0.33 nm
D
0.36 nm
COMEDK Subjects