Which of the following can liberate photo electrons when they fall on certain metals?
A. Alpha particles
B. Beta particles
C. Gamma particles
D. X-ray particles
Answer:D
Which of the following can liberate photo electrons when they fall on certain metals?
A. Alpha particles B. Beta particles C. Gamma particles D. X-ray particles
Explanation: X-rays can liberate photo electrons when they fall on certain metals. They penetrate through certain substances that are opaque to ordinary light.