PHYSICAL SCIENCE > PHYSICAL SCIENCE
1) Electric current in a metal wire is due to the flow of:
A) ProtonsB) Electrons
C) IonsD) none of these
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Answer : Electrons


2) In amplitude modulation :
A) carrier frequency is changedB) carrier amplitude is changed
C) three sidebands are producedD) fidelity is improved
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Answer : three sidebands are produced


3) The curve traced by ,1 point moving on a plane in one direction, towards a fixed point while also moving around that point is called ?
A) trochoidB) Spiral
C) ParabolaD) Catenary
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Answer : Spiral


4) Which of the following is a cycle consisting of one constant pressure, one constant volume and two isentropic processes ?
A) Carnot cycleB) Stirling cycle
C) Otto cycleD) Diesel cycle
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Answer : Diesel cycle


5) What is the SI unit of absolute permittivity of a medium ?
A) J/CB) C2/(Nm2)
C) C2/(Nm)D) (Nm)/C2
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Answer : J/C


6) The velocity at which the flow changes from laminar to turbulent for the case of a given liquid at a given temperature and in a given pipe, is known as :
A) Turbulence velocityB) Critical velocity
C) Reynolds velocityD) Froude velocity
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Answer : Critical velocity


7) The function of heavy water in a nuclear reactor is to
A) Slow down the speed of neutronsB) Increase the speed of neutrons
C) Cool down the reactorD) Stop the nuclear reaction
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Answer : Slow down the speed of neutrons


8) The efforts to detect the existence of Higgs boson particle have become frequent news in the recent past. What is/are the importance/ importances of discovering this particle?
1) It will enable us to understand as to why elementary particles have mass
2) It will enable us in the near future to develop the technology of transferring matter from one point to another without traversing the physical space between them
3) It will enable us to create better fuels for nuclear fission
4) -
A) 1 only
B) 2 and 3 only
C) 1 and 3 only
D) 1, 2 and 3
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Answer : 1 only


9) The known forces of nature can be divided into four classes, viz., gravity, electromagnetism, weak nuclear force and strong nuclear force. With reference to them, which one of the following statements is not correct?
A) Gravity is the strongest of the fourB) Electromagnetism acts only on particles with an electric charge
C) Weak nuclear force causes radioactivityD) Strong nuclear force holds protons and neutrons inside the nucleus of an atom
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Answer : Gravity is the strongest of the four


10) Rainbow is produced when sunlight falls on drops of rain. Which of the following physical phenomena are responsible for this?
1) Dispersion
2) Refraction
3) Internal reflection
4) -
A) 1 and 2 only
B) 2 and 3 only
C) 1 and 3 only
D) 1, 2 and 3
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Answer : 1, 2 and 3