Physics MCQs

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In 1930, C.V. Raman became the first person from Asia to be awarded a Nobel Prize in any field of science. CV Raman made significant contributions to the field of optics. He is best known for his discovery of the Raman effect, which is the scattering of light by molecules. This phenomenon is now known as Raman scattering. The date of the discovery, February 28, is now celebrated as National Science Day in India.

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An ideal fluid hypothetical fluid should contain Zero Viscosity & Zero Compressibility. Almost all fluids will not have zero viscosity and zero compressibility.

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Radio waves are a type of electromagnetic radiation with wavelengths in the electromagnetic spectrum longer than infrared light. Radio waves have frequencies as high as 300 gigahertz to as low as 30 hertz. It is used to measure the speed of an approaching car.

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When a barometer is taken down into a coal mine, the mercury level rises. This is because the temperature increases as you move down the Earth’s crust. There is also very little wind, so the warmth can’t distribute the temperature and moderate it.  A barometer is an instrument that measures pressure. In a coal mine, the pressure is higher than normal pressure. When a barometer is taken down into a coal mine, it shows a greater reading.

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The weight of a person becomes zero in a lift. Lift moves down with an acceleration of 9.8 meter per sq. second.

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This question is related to Antoine equation. Water to get boil, its vapour pressure must reach to its surrounding pressure. In a pressure cooker, it boils at the highest temperature. Elevation of Kochi is 0 m, ooty is 2,486 m, Mount Abu is 1,200 m, New Delhi is 216 m, Shimla is 2,205 m. So comparing all of them, water will boil at lowest temperature at ooty, followed by Shimla, Mount Abu , New Delhi and Kochi. This is because , higher we go lower is the atmospheric pressure and lower is the point where water`s vapour pressure gets equal to the atmospheric pressure.

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A Balloon filled with a gas such as Hydrogen gas is much lighter in weight than the weight of air displaced by it. So the buoyant force exerted by the air on a balloon is greater than the weight of the balloon. The hydrogen gas which is lighter than air enables the balloon to float.

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An Electric generator works on the principle of Faraday’s law of Electromagnetic Induction. An electric generator uses mechanical energy to generate electricity applying Faraday’s law of induction. It spins a coil at a constant rate in a magnetic field to induce an oscillating emf.

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The largest practical unit of mass is called as Chandra Shekhar Limit (C.S.L) which is equivalent to 1.4 times the mass of Sun. Chandrasekhar limit is the maximum mass theoretically possible for a stable white dwarf star. This limiting value was named after Indian-born astrophysicist Subrahmanyan Chandrasekhar, who formulated it in 1930. Using Albert Einstein’s special theory of relativity and the principles of quantum physics, Chandrasekhar showed that it is impossible for a white dwarf star, which is supported solely by a degenerate gas of electrons, to be stable if its mass is greater than 1.44 times the mass of the Sun.

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Triple point of water is the temperature at which ice, water and water vapours coexist. The value of Triple point of water is 273.16 K Kelvin is the S.I unit of Temperature represented by symbol K.