Chapter 14, Problem 17RQ

Solution

To determine: The evidence for the wave and particle nature of light.

Amnswer:

Interference and diffraction of light give evidence to the wave nature of light while photoelectric effect gives evidence to the particle nature of light.

Explanation:

When a beam of monochromatic light passed through a single slit is made to fall on a screen, alternate dark and bright fringes are observed. The light rays bend as it passed through the slit. A diffraction pattern of bright and dark fringes was seen due to the constructive and destructive interference of light waves. If the light had only particle nature, a single spot on the screen would have been the result.

In the photoelectric effect, electrons are ejected from a metal surface if the light of a certain frequency is allowed to fall on the metal surface. The emission of electrons is the evidence of the particle nature of light. Light is a form of particles called photons and each photon caused the emission of an electron.

Conclusion:

Therefore, interference and diffraction of light give evidence to the wave nature of light while photoelectric effect gives evidence to the particle nature of light.