Scientists & Inventions

11. Which of the following pairs of physical phenomenon and the discoverer

Which of the following pairs of physical phenomenon and the discoverer is/are correctly matched ?

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1.James Chadwick:Photoelectric effect
2.Albert Einstein:Neutron
3.Marie Curie:Radium

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1, 2 and 3
1 and 2 only
2 and 3 only
3 only
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Only the third pair is correctly matched.
– James Chadwick discovered the neutron in 1932. The photoelectric effect was explained by Albert Einstein in 1905, building on observations by Heinrich Hertz.
– Albert Einstein is famous for his theory of relativity and his explanation of the photoelectric effect, not the discovery of the neutron.
– Marie Curie, along with her husband Pierre Curie, discovered the elements polonium and radium in 1898.
Marie Curie was a Polish and naturalized-French physicist and chemist who conducted pioneering research on radioactivity. She was the first woman to win a Nobel Prize, the first person and only woman to win the Nobel Prize twice, and the only person to win the Nobel Prize in two different scientific fields.

12. Who among the following has explained the phenomenon of photo-electric

Who among the following has explained the phenomenon of photo-electric effect ?

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Max Planck
Albert Einstein
Neils Bohr
Ernest Rutherford
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The phenomenon of the photo-electric effect, where electrons are emitted from a metal surface when light shines on it, was explained by Albert Einstein in 1905. He proposed that light energy is quantized into discrete packets called photons and that the energy of each photon is proportional to its frequency (E = hf, based on Planck’s work). This revolutionary idea successfully explained the observed characteristics of the photo-electric effect, such as the existence of a threshold frequency and the dependence of emitted electron energy on the frequency of light, not its intensity.
– Max Planck introduced the concept of energy quantization (quanta).
– Albert Einstein applied the concept of light quanta (photons) to explain the photo-electric effect.
– Niels Bohr developed the quantum model of the atom.
– Ernest Rutherford discovered the atomic nucleus.
Einstein received the Nobel Prize in Physics in 1921 specifically for his services to Theoretical Physics, and especially for his discovery of the law of the photo-electric effect. This work was crucial in the development of quantum mechanics.

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13. The phenomenon of radioactivity was first discovered by

The phenomenon of radioactivity was first discovered by

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Marie Curie
Henri Becquerel
Frederick Soddy
Ernest Rutherford
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The phenomenon of radioactivity was first discovered by French physicist Henri Becquerel in 1896. He observed that uranium salts spontaneously emitted radiation that could expose photographic plates, even when the salts were wrapped in opaque paper.
Henri Becquerel’s accidental discovery of radiation from uranium marked the beginning of the study of radioactivity.
Marie Curie and her husband Pierre Curie followed up on Becquerel’s work, isolating new radioactive elements like polonium and radium and coining the term “radioactivity”. They, along with Becquerel, shared the Nobel Prize in Physics in 1903 for their work on radioactivity. Ernest Rutherford later characterized the different types of radiation (alpha, beta, gamma) and developed the nuclear model of the atom. Frederick Soddy is known for his work on isotopes and their role in radioactivity.

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14. Who among the following is known to be the first one to consider the r

Who among the following is known to be the first one to consider the role of inertia in motion?

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Galileo Galilei
Isaac Newton
Albert Einstein
Nicolaus Copernicus
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Galileo Galilei (1564-1642) is widely credited with being the first to formulate a clear concept of inertia. Through experiments and thought experiments, particularly concerning motion on inclined planes, he concluded that an object in motion would continue in motion with constant velocity in the absence of forces. This contradicted the prevailing Aristotelian view that force was required to maintain motion. While Isaac Newton later formalized this as his First Law of Motion (the law of inertia), Galileo’s work laid the essential groundwork and is considered the first significant step in understanding inertia.
– Inertia is the property of matter resisting changes in motion.
– Galileo’s work challenged Aristotelian physics regarding motion.
– Galileo’s experiments and thought experiments led him to the concept of inertia.
– Newton later formalized inertia as his First Law of Motion.
Before Galileo, the common belief based on Aristotle was that objects required a continuous force to stay in motion. Galileo’s understanding shifted this paradigm, proposing that motion persists unless acted upon by external forces like friction or gravity.

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15. The Nobel Prize in Physics for the year 2016 was given to

The Nobel Prize in Physics for the year 2016 was given to

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David J. Thouless
F. Duncan M. Haldane
J. Michael Kosterlitz
All of them
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The Nobel Prize in Physics for the year 2016 was jointly awarded to David J. Thouless, F. Duncan M. Haldane, and J. Michael Kosterlitz.
The prize was awarded for their theoretical discoveries of topological phase transitions and topological phases of matter, which have opened the door to an unknown world where matter can assume strange states.
Their work used advanced mathematical methods to study unusual phases, or states, of matter, such as superconductors, superfluids, or thin magnetic films. The discoveries have implications for the design of new materials with novel properties.

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16. Consider the following statement: “If you feel you are trapped in a bl

Consider the following statement:
“If you feel you are trapped in a black hole, don’t give up. There is a way out.”
Who among the following made the above statement?

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Albert Einstein
Stephen Hawking
C. V. Raman
Abdus Salam
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The statement, “If you feel you are trapped in a black hole, don’t give up. There is a way out,” was made by physicist Stephen Hawking.
– Stephen Hawking was a theoretical physicist and cosmologist known for his groundbreaking work on black holes and the origin of the universe.
– Despite his severe physical disability (ALS), he continued his scientific research and public engagement throughout his life.
– This particular quote reflects his scientific understanding of black holes and can also be interpreted metaphorically about facing difficulties in life.
Stephen Hawking’s major scientific contributions include his theorems on gravitational singularities in the framework of general relativity and the theoretical prediction that black holes emit radiation, often called Hawking radiation. He authored popular science books like ‘A Brief History of Time’.

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17. Who among the following is not a recipient of the Nobel Prize in Phy

Who among the following is not a recipient of the Nobel Prize in Physics in 2022?

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Alain Aspect
John F. Clauser
Klaus Hasselmann
Anton Zeilinger
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Klaus Hasselmann was a recipient of the Nobel Prize in Physics in 2021, shared with Syukuro Manabe and Giorgio Parisi. The Nobel Prize in Physics in 2022 was awarded jointly to Alain Aspect, John F. Clauser, and Anton Zeilinger.
Alain Aspect, John F. Clauser, and Anton Zeilinger received the 2022 Nobel Prize in Physics for their experiments with entangled photons, establishing the violation of Bell inequalities and pioneering quantum information science.
Klaus Hasselmann’s Nobel Prize in 2021 was recognized for “for the physical modelling of Earth’s climate, quantifying variability and reliably predicting global warming”.

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18. Who amongst the following is a pioneer in discovering the heating effe

Who amongst the following is a pioneer in discovering the heating effect of electric current ?

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Isaac Newton
Galileo Galilei
James P. Joule
J.J. Thomson
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James Prescott Joule was a physicist who studied the nature of heat and its relationship to mechanical work. He is best known for establishing that electric current produces heat when it flows through a resistance, quantifying this effect in what is now known as Joule’s law of heating, which states that the heat produced is proportional to the square of the current, the resistance, and the time ($H \propto I^2Rt$).
James P. Joule’s experiments demonstrated the relationship between electric current flow through a resistor and the heat generated, leading to Joule’s Law of Heating.
Isaac Newton formulated laws of motion and universal gravitation. Galileo Galilei made significant contributions to astronomy and the study of motion. J.J. Thomson discovered the electron.

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19. The fact that the planets move around the Sun, not in circles but in e

The fact that the planets move around the Sun, not in circles but in ellipses, was first demonstrated by

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Galileo
Martin Luther
Johannes Kepler
Copernicus
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The correct answer is C) Johannes Kepler. The German astronomer Johannes Kepler was the first to demonstrate that the planets move around the Sun in elliptical orbits.
– Nicolaus Copernicus proposed the heliocentric model where planets orbit the Sun, but he assumed the orbits were perfect circles.
– Galileo Galilei provided telescopic observations that supported the heliocentric model but did not discover elliptical orbits.
– Johannes Kepler, using the detailed astronomical data collected by Tycho Brahe, formulated his three laws of planetary motion between 1609 and 1619.
– Kepler’s First Law states that the orbit of a planet is an ellipse with the Sun at one of the two foci.
Kepler’s laws were a fundamental breakthrough in astronomy, replacing the ancient concept of circular orbits and providing a mathematical description of planetary motion that was later explained by Isaac Newton’s law of universal gravitation.

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