Q.1:- Which one of the following phenomena is used in optical fibres ?
- Scattering
- Successive Reflection
- Refraction
- Total Internal Reflection
Ans:- (d) Total Internal Reflection
Q.2:- The human eyes has a lens which has a ?
- Soft portion at its centre
- Hard surface
- Varying refractive index
- Constant refractive index
Ans:- (d) Constant refractive index
Q.3:- Longitudinal waves do not exhibit ?
- Refraction
- Reflection
- Diffraction
- Polarization
Ans:- (d) Polarization
Q.4:- The image formed on the retina of a human eye is ?
- Virtual and inverted
- Virtual and erect
- Real and erect
- Real and inverted
Ans:- (d) Real and inverted
Q.5:- Cylindrical lens is used by a person suffering from ?
- Astigmatism
- Myopia
- Hypermetropia
- Presbyopia
Ans:- (a) Astigmatism
Q.6:- The phenomenon of splitting white light into seven colours is called ?
- Reflection
- Refraction
- Refractive index
- Dispersion
Ans:- (d) Dispersion
Q.7:- The resistance of material increases with temperature. It is a ?
- Metal
- Insulator
- Semiconductor
- None of these
Ans:- (a) Metal
Q.8:- Electron volt (eV) is a unit of ?
- Energy
- Potential
- Current
- Charge
Ans:- (a) Energy
Q.9:- The resistance of an ideal voltmeter is ?
- Zero
- Very low
- Very high
- Infinite
Ans:- (a) Zero
Q.10:- Equal charges are given to two spheres of different radii. The potential will be ?
- More on smaller sphere
- More on bigger sphere
- Equal on both the sphere
- None of these
Ans:- (a) More on smaller sphere
Q.11:- Good resistance coils are made of ?
- Copper
- Manganin
- Gold
- Silver
Ans:- (b) Manganin
Q.12:- The filament of bulb is of ?
- Mercury
- Copper
- Tungsten
- None of these
Ans:- (c) Tungsten
Q.13:- A thermoelectric refrigerator works on ?
- Jule Effect
- Seebeck Effect
- Peltier Effect
- None of these
Ans:- (c) Peltier Effect
Q.14:- A small piece of an unmagnetised material gets repelled when it is brought near a powerful magnet the material is ?
- Paramagnetic
- Diamagnetic
- Ferromagnetic
- Non Magnetic
Ans:- (b) Diamagnetic
Q.15:- A source of magnetic field is ?
- A static electric charge
- A moving electric charge
- A current loop
- Both (b) and (c)
Ans:- (d) Both (b) and (c)
Q.16:- Which of the following is most suitable for the core of an electromagnet ?
- Air
- Soft Iron
- Steel
- None of these
Ans:- (b) Soft Iron
Q.17:- A diode as a rectifier converts ?
- AC to DC
- DC to AC
- Varying DC into constant DC
- High Voltage into low voltage and vice-versa
Ans:- (a) AC to DC
Q.18:- The conductivity of a super-conductor is ?
- Infinite
- Small
- Zero
- Large
Ans:- (a) Infinite
Q.19:- The cause of fractional atomic weights of elements is the presence of ?
- Isobars
- Isotopes
- Isotones
- None
Ans:- (b) Isotopes
Q.20:- With the rise of temperature, the specific resistance of semiconductor ?
- Increases
- Remains Unchanged
- Decreases
- None of these
Ans:- (c) Decreases
Q.21:- Cathode rays enter an electric field normal to the lines of force. Then their path in the electric field is ?
- Straight Line
- Ellipse
- Circle
- Parabola
Ans:- (d) Parabola
Q.22:- At zero degree kelvin a piece of germinium ?
- Becomes semiconductor
- Becomes good conductor
- Becomes bad conductor
- None of these
Ans:- (c) Becomes bad conductor
Q.23:- Which of the following is not a semiconductor ?
- Germinium
- Silicon
- Arsenic
- All of these
Ans:- (c) Arsenic
Q.24:- The space waves which are affected seriously by atmospheric conditions are ?
- MF0
- HF
- VHF
- UHF
Ans:- (d) UHF
Q.25:- The technique of collecting information about an object from a distance without making physical contact with it is ?
- Remote Sensing
- Remote Control
- Remote Accessing
- Space Shuttle
Ans:- (a) Remote Sensing
