Railway Science (Physics-Discoveries)

Total Questions: 19

1. Who invented the modern mercury thermometer with a standardised scale? [RRB NTPC CBT - I (12/01/2021) Morning]

Correct Answer: (c) Daniel Gabriel Fahrenheit
Solution:

He is Known as the inventor of the Alcohol thermometer, Mercury - in - glass thermometer and Fahrenheit temperature scale. Celsius was invented by Anders Celcius (Award - Fellow of the Royal Society). Galileo Galilei is famous for his telescope discoveries.

2. Name the world famous scientist known for his theory of relativity. [RRB NTPC CBT - I (13/01/2021) Morning]

Correct Answer: (c) Albert Einstein
Solution:

According to this theory, mass can be converted into energy and vice-versa. i.e., E = mc² , Where, c = velocity of light. E is the energy equivalent of mass m. Christian Bernard was a South African Cardiac Surgeon who performed the world's first human-to-human Heart transplant operation. John Dalton’s important contribution was the atomic theory. Thomas Alva Edison's invention is well known for his invention of the light bulb.

3. Which British physicist was awarded the Nobel Prize in Physics in 1906 for his work on discovery of electrons? [RRB NTPC CBT - I (16/01/2021) Morning]

Correct Answer: (b) J J Thomson
Solution:

James Chandwick discovered neutrons in 1932. Niels Bohr proposed a model of the atom in 1913. Ernest Rutherford postulated the nuclear structure of the atom in 1911, discovered alpha and beta rays, and proposed the laws of radioactive decay.

4. In 1752, which American scientist showed that lightning and the spark from your clothes are essentially the same phenomena? [RRB NTPC CBT - I (16/01/2021) Morning]

Correct Answer: (b) Benjamin Franklin
Solution:

Archimedes is known for his formulation of a hydrostatic principle (known as Archimedes' principle) and a device for raising water, still used, known as the Archimedes screw. Galileo Galilei is famous for his telescopic discoveries. Thomas Edison is famous for the inventions such as the incandescent light bulb, the phonograph, and the motion picture camera, as well as improving the telegraph and telephone.

5. Who proposed the laws of planetary motion? [RRB NTPC CBT - I (20/01/2021) Morning]

Correct Answer: (d) Johannes Kepler
Solution:

Isaac Newton - Laws of motion. Roger Bacon - The first to describe the process of making gunpowder. Galileo - The first person to record observations of the sky made with the help of a telescope.

6. Which of the following was discovered by Henri Becquerel? [RRB NTPC CBT - I (04/02/2021) Evening]

Correct Answer: (d) Radioactivity
Solution:

Henri Becquerel was a physicist and Noble laureate. The SI unit of radioactivity is becquerel (Bq). Awards : Nobel Prize in Physics (1903), Rumford Medal(1900). Other scientists and their discoveries : Infrared Radiation (William Herschel), UV radiation (Johann Wilhelm Ritter), Conductivity (Stephen Gray).

7. Who said the following statement? “We owe a lot to the Indians, who taught us how to count, without which no worthwhile scientific discovery could have been made!” [RRB NTPC CBT - I (11/02/2021) Evening]

Correct Answer: (d) Albert Einstein
Solution:

(Theoretical physicist) is best known for his theory of relativity. E=mc², showed the equivalence of energy (E) and mass (m) and laid the foundation for advancements in nuclear physics. Award - Nobel Prize in Physics (1921). Frederick Herzberg proposed two-factor theory in the field of human resource management and organizational behavior.

8. Who was the first person to obtain a spectrum by passing light through a prism? [RRB NTPC CBT - I (16/02/2021) Evening]

Correct Answer: (d) Issac Newton
Solution:

Other achievements - Discovered the Laws of Gravity, Built the first working reflecting telescope. Visible Radiation was discovered by Isaac Newton. Pierre Curie discovered radium and polonium in 1898 AD. Paul Villard - Discovered Gamma Rays. Benjamin Franklin is known for the lightning rod, bifocals, and the Franklin stove, among other inventions.

9. Long Radio waves were discovered by- [RRB NTPC CBT - I (07/03/2021) Evening]

Correct Answer: (a) Guglielmo Marconi
Solution:

(Nobel Prize in physics 1909) created a practical radio wave based wireless telegraph system. Heinrich Hertz proved the existence of radio waves in the late 1880s. W C Roentgen (Nobel Prize in physics in 1901) discovered X-rays in 1895.

10. Who among the following noticed the deflection of the compass needle every time current was passed through the wire? [RRB NTPC CBT - I (26/07/2021) Evening]

Correct Answer: (d) Hans Christian Oersted
Solution:

The deflection in the needle becomes opposite when the direction of the current is reversed. He discovered electromagnetism in 1820. Oersted's Law - Moving charges or currents produced a magnetic field in the surrounding space. SI units: Current - Ampere (A), Magnetic field - Tesla (T).