Photoelectric emission was discovered by Heinrich Hertz during his exp…

Question

Photoelectric emission was discovered by Heinrich Hertz during his experiments on

Accepted Answer

A. {'text': 'Production of electromagnetic waves by spark discharge', 'label': 'A'}

1. Hertz in 1887 was investigating electromagnetic-wave generation by spark discharge.
2. He observed high-voltage sparks were enhanced when the emitter plate was illuminated by UV light.
3. This unexpected observation was the discovery of the photoelectric effect.
4. Ironically he was studying wave nature of light but discovered the effect that later helped prove its particle nature.
_Source: NCERT Class 12 Physics, Ch 11 "Dual Nature of Radiation and Matter", §11.3.1_

Answer

{'text': 'Radioactivity of newly discovered heavy elements', 'label': 'B'}

Answer

{'text': 'Cathode rays in the low-pressure discharge tubes', 'label': 'C'}

Answer

{'text': 'X-rays emitted from certain heated metallic materials', 'label': 'D'}