Question

Who discovered the electron?

• A. J. J. Thomson
• B. Copernicus
• C. Galileo
• D. J. B. Narlikar

Hint:

Link discoveries with scientists and their experiments for easier recall, e.g., J. J. Thomson - cathode ray experiments - electron discovery.

Answer 1

The Correct Option is A

Step 1: Understand what the electron is.
The electron is a fundamental subatomic particle with a negative electric charge, which is a key constituent of atoms.
Step 2: Historical context of the discovery.
In the late 19th century, scientists were investigating the nature of electricity and matter. The concept of atoms being indivisible was prevalent but being challenged.
Step 3: J. J. Thomson’s experiments.
In 1897, J. J. Thomson conducted experiments using cathode ray tubes. He observed that cathode rays were deflected by electric and magnetic fields, indicating they were charged particles.
He measured the charge-to-mass ratio of these particles and concluded that they were much smaller than atoms, thus discovering the electron.
Step 4: Elimination of other options.
Copernicus was an astronomer who proposed the heliocentric model of the solar system.
Galileo contributed to physics and astronomy but did not discover the electron.
J. B. Narlikar is a modern astrophysicist known for work in cosmology, not for discovering electrons. Conclusion:
J. J. Thomson is credited with the discovery of the electron as the first subatomic particle, revolutionizing atomic theory.