Intensity vs Current — Practice Quiz

Question 1

If the intensity of light incident on a photocathode is doubled, the photoelectric current:

Accepted Answer

Doubles

Answer

Halves

Answer

Remains same

Answer

Becomes zero

Question 2

Doubling the intensity of light affects:

Accepted Answer

Number of photoelectrons emitted per second

Answer

K_max

Answer

Stopping potential

Answer

Threshold frequency

Question 3

Saturation current is reached when:

Accepted Answer

All emitted photoelectrons are collected by anode

Answer

Voltage reaches threshold

Answer

Intensity is doubled

Answer

Frequency exceeds threshold

Question 4

A photocell receives light of intensity 10 W/m² and frequency 6×10¹⁴ Hz over area 1 cm². Photons arriving per second:

Accepted Answer

≈ 2.5 × 10¹⁵

Answer

≈ 2.5 × 10¹²

Answer

≈ 6.6 × 10⁻¹⁹

Answer

≈ 10⁵

Question 5

At a fixed frequency, plot of photocurrent vs intensity is:

Accepted Answer

Linear through origin

Answer

Hyperbola

Answer

Parabolic

Answer

Sinusoidal