English Assam PSC (Pre) 2015 Meghalaya PSC (Pre) 2019 UPPCS (Pre) 2003
Q2261. A liquid is flowing in a streamlined manner through a cylindrical pipe. Alongwith a section containing the axis of the pipe, the flow profile will be
A Diagram A — see source PDF page 530 B Diagram B — see source PDF page 530 C Diagram C — see source PDF page 530 D Diagram D — see source PDF page 530
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Correct answer: Diagram D — see source PDF page 530
Concept note
Q2262. Assertion (A): An iron ball floats on mercury but gets immersed in water. Reason (R): The specific gravity of iron is more than that of mercury. Code
A Both (A) and (R) are true and (R) is the correct explanation of B Both (A) and (R) are true, but (R) is not the correct explanation of (A) C (A) is true, but (R) is false D (A) is false, but (R) is true
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Correct answer: (A) is true, but (R) is false
English UPPCS (Pre) 2003 UP UDA/LDA (Pre) 2002
Q2263. Assertion (A): When a ship enters a sea from a river, it rises a little. Reason (R): The density of sea water is greater than that of river water. In the context of the above statements, which of the following is true?
A Both (A) and (R) are true and (R) is the correct explanation of B Both (A) and (R) are true, but (R) is not the correct explanation of (A) C (A) is true, but (R) is false D (A) is false, but (R) is true
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Correct answer: Both (A) and (R) are true and (R) is the correct explanation of
English UPPCS (Mains) 2005
Q2264. The wavelength extension of visible light is
A Between 200-900 nm B Between 250-850 nm C Between 300-800 nm D Between 390-780 nm
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Correct answer: Between 390-780 nm
Q2265. Human eye is most sensitive to visible light of the wavelength
A 6050 Å B 5500 Å C 4500 Å D 7500 Å
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Correct answer: 5500 Å
English Uttarakhand PCS (Pre) 2012
Q2266. Which of the following radiations has the highest energy per quantum?
A 320-400 nm B 200-280 nm C 280-320 nm D 400-600 nm
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Correct answer: 200-280 nm
English 53rd to 55th BPSC (Pre) 2011
Q2267. The visible range of solar radiation is
A 100-400 nm B 400-700 nm C 740-10000 nm D None of the above
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Correct answer: 400-700 nm
English 42nd BPSC (Pre) 1997, 98
Q2268. The nature of radiation of light is
A Like wave B Like particle C Like both of wave and particle D Like neither of wave nor of particle
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Correct answer: Like both of wave and particle
Q2269. Light appears to travel in a straight line because
A It consists of small particles B The velocity of light is very large C The wavelength of light is very small D Light is reflected by the surroundings
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Correct answer: The wavelength of light is very small
English Jharkhand PCS (Pre) 2003 43rd BPSC (Pre) 1999
Q2270. The speed of light in vacuum is nearly
A 3 × 1010 m/s B 3 × 108 m/s C 3 × 108 km/s D 3 × 108 light years
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Correct answer: 3 × 108 m/s
Q2271. Velocity of light is maximum in
A Diamond B Water C Vacuum D Hydrogen
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Correct answer: Vacuum
Q2272. The speed of light will be minimum while passing through
A Glass B Vacuum C Water D Air
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Correct answer: Glass
English UPPCS (Mains) 2006 42nd BPSC (Pre) 1997
Q2273. The time taken to reach the Sunlight up to the surface of Earth is approximately
A 4.2 sec B 4.8 sec C 8.5 minutes D 3.6 hours
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Correct answer: 8.5 minutes
Q2274. When light waves pass from air to glass the variable affected are
A Wavelength, frequency and velocity B Velocity and frequency C Wavelength and frequency D Wavelength and velocity
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Correct answer: Wavelength and velocity
English UPPCS (Mains) 2003
Q2275. When light passes from one medium to another medium, which one of the following does not change?
A Intensity B Velocity C Wavelength D Frequency
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Correct answer: Frequency
Q2276. Which one of the following energy conversions takes place in carrying out the process of photosynthesis?
A Light to chemical energy B Light to thermal energy C Thermal to biochemical energy D Heat to kinetic energy
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Correct answer: Light to chemical energy
Q2277. The gas used in discharge tubes for optical decoration and advertising is
A Carbon dioxide B Ammonia C Sulphur dioxide D Neon
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Correct answer: Neon
Q2278. The formation of glittering colours in thin foam of soap is the result of which of the following phenomenon?
A Total reflection and interference B Total refraction and dispersion C Diffraction and dispersion D Polarization and interference
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Correct answer: Total reflection and interference
Q2279. Total internal reflection can take place when light travels from
A Diamond to glass B Water to glass C Air to water D Air to glass
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Correct answer: Diamond to glass
English UP UDA/LDA (Pre) 2010 UPPCS (Spl)(Pre) 2008 IAS (Pre) 1995
Q2280. Optical fibre works on the principle of
A Total internal reflection B Refraction C Scattering D Interference
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Correct answer: Total internal reflection