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

• A Fathometer is used to measure the depth of the ocean, sea, or any body of water.
• It determines the distance from the water surface to the seabed.
• The instrument works using sound waves (echo sounding).
• It measures the time taken for sound waves to travel to the seabed and return.

Additional information:

• Galvanometer → Measures electric current
• Barometer → Measures atmospheric pressure
• Thermometer → Measures temperature
• Hygrometer → Measures humidity

Last verified on 06-07-2026

Explanation

• The laws of magnetic induction were given by Michael Faraday.
• Faraday proposed these laws in 1831 after discovering electromagnetic induction.
• The laws explain that a changing magnetic field induces an electromotive force (EMF) in a conductor.
• These laws are the foundation of electric generators and transformers.

Last verified on 06-07-2026

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