Explanation

• Sir James Chadwick discovered the neutron in 1932.
• He was a British physicist.
• His discovery completed the basic picture of the atomic nucleus.
• He received the Nobel Prize in Physics in 1935 for this discovery.

Additional information:

• J. J. Thomson – Electron (1897)
• Ernest Rutherford – Atomic nucleus (1911) and Proton (1917)

Last verified on 03-07-2026

Explanation

• Karl Landsteiner discovered the ABO Blood Group System in 1900.
• He was an Austrian scientist and physician.
• His discovery made safe blood transfusions possible.
• He received the Nobel Prize in Physiology or Medicine in 1930 for his work.

Last verified on 01-07-2026

Explanation

• The magnitude of an earthquake is measured by the Richter scale.
• It measures the energy released by an earthquake.
• The Richter scale was developed in 1935 by Charles F. Richter.
• It is used in seismology (the study of earthquakes).

Last verified on 30-06-2026

Explanation

• Discoverer: Alexander Fleming
• Year of discovery: 1928
• Place: St. Mary's Hospital, London
• First patient treated with penicillin: Albert Alexander
• Date of first treatment: 12 February 1941

Last verified on 01-07-2026

Explanation

• The atmospheric pressure at any place is measured by a Barometer.
• The barometer was invented by Evangelista in 1644.

Last verified on 10-03-2026