Que- Two sources of light are coherent if they emit rays of
a. same wavelength
b. same amplitude of vibration
c. same wave length with constant phase difference
d. same amplitude and wavelength
Answer- same wave length with constant phase difference
Que- When crest of one wave falls over the trough of the other wave this phenomenon is known as
a. polarization
b. constructive interference
c. destructive interference
d. diffraction
Answer- destructive interference
Que- In Young double slit experiment, if white light is used
a. alternate dark and bright fringes will be seen
b. coloured fringes will be seen
c. no interference fringes will be seen
d. impossible to predict
Answer- coloured fringes will be seen
Que- The velocity of light was determined accurately by
a. Newton
b. Michelson
c. Huygen
d. Young
Answer- Michelson
Que- In an interference pattern
a. bright fringes are wider than dark fringes
b. dark fringes are wider than bright fringe
c. both dark and bright fringes are of equal width
d. central fringes are brighter than the outer fringes
Answer- both dark and bright fringes are of equal width
Que- appearance of colour in thin films is due to
a. diffraction
b. dispersion
c. interference
d. polarization
Answer- interference
Que- The blue colour of the sky is due to
a. diffraction
b. reflection
c. polarization
d. scattering
Answer- scattering
Que- A light ray traveling form rarer to denser medium suffers a phase change of
a. 60 Degree
b. 90 Degree
c. 180 Degree
d. 45 Degree
Answer- 180 Degree
Que- When one mirror of a Michelson Interferometer is moved a distance of 0.5 mm we observe 2000 fringes. What will be wavelength of light used?
a. 5000 nm
b. 5000A?
c. 500m
d. 2000um
Answer- 5000A?
Que- Diffraction effect is
a. more for a round edge
b. less for a round edge
c. more for a sharp edge
d. less for a sharp edge.
Answer- more for a sharp edge
Que- Wavelength of X-rays falling at glancing angle of 30 Degree on a crystal with atmic spacing 2 x 10-10 for the fist order diffraction is
a. 4 x 10-10 m
b. 2 x 10-10 m
c. 0.02x10-10m
d. 20x10-10m
Answer- 2 x 10-10 m
Que- A diffraction grating has 500 lines per mm. Its slit spacing or grating element will be equal to
a. 500 mm
b. 5 x 10-3 mm
c. 2 x 10-5 mm
d. 2 x 10-3 mm
Answer- 2 x 10-3 mm
Que- In a plane polarized light
a. vibration in all direction
b. vibration in two mutually perpendicular directions
c. vibration take place in a direction perpendicular to the direction of propagation of light
d. no vibration at all
Answer- vibration take place in a direction perpendicular to the direction of propagation of light
Que- Light on passing through a Polaroid is
a. plane polarized
b. un-polarized
c. circularly polarized
d. elliptically polarized
Answer- plane polarized
Que- Which one of the following cannot be polarized?
a. radio waves
b. ultraviolot rays
c. X-rays
d. sound waves
Answer- sound waves
Que- Diffarction fringes are
a. equally spaced
b. distance between them increases
c. distance between then decreases
d. they are adjacent with no space in between
Answer- distance between then decreases
Que- In monochromatic red light a blue book will probably appear to be
a. black
b. purple
c. green
d. no scientific reasoning available
Answer- black
Que- A thing that emits its own light is
a. luminous
b. non-luminous
c. incandescent
d. bright
Answer- luminous
Que- In double slit experiment if one of the two slit is covered then
a. no interference fringes are observed
b. no diffraction fringes are observed
c. no fringes observed
d. interference pattern not disturbed
Answer- no interference fringes are observed
Que- gives the definition of metre in terms of wavelength of red cadmium light
a. Newton
b. Einstein
c. Michelson
d. Galileo
Answer- Michelson
Que- In the shadow of a ball the central portion appears bright that happens due to
a. Interference
b. Diffraction
c. Polarization
d. Refraction
Answer- Diffraction
Que- Which experiment shows that wavelength of light is smaller than that of sound
a. Diffraction
b. Polarization
c. Interference
d. Reflection
Answer- Diffraction
Que- Crystals of a material can behave as
a. Convex lens
b. Interferometer
c. Diffraction grating
d. Concave
Answer- Diffraction grating
Que- A lens which converges a beam of parallel rays to a point is called
a. diverging (or concave) lens
b. converging (or convex) lens
c. plano concave lens
d. plano convex lens
Answer- converging (or convex) lens
Que- A point where the incident parallel rays of light converge or appear to diverge after passing through a lens is called
a. center of curvature
b. focus
c. optical center
d. aperture
Answer- focus
Que- The diameter of a lens is called
a. focal length
b. principal axis
c. aperture
d. radius of curvature
Answer- aperture
Que- In going form a denser to rarer medium a ray of light is
a. undeviated
b. bent away form the normal
c. bent towards the normal
d. polarized
Answer- bent away form the normal
Que- Unit of power of a lens is
a. meter
b. watt
c. dioptre
d. horsepower
Answer- dioptre
Que- Dioptre power of an concave lens of 10 cm focal length is
a. 10 dioptre
b. 10 dioptre
c. 1 / 10 dioptre
d. 1 / 10 dioptre
Answer- 10 dioptre
Que- The power of a concave lens is
a. real
b. virtual
c. positive
d. negative
Answer- negative
Que- The minimum distance between an object and its real image in a convex lens is
a. 2 f
b. 2.5 f
c. 3f
d. 4f
Answer- 4f
Que- If an object is placed away from 2f of a converging lens then the image will be
a. real and erect
b. virtual and erect
c. real and inverted
d. virtual
Answer- real and inverted
Que- A convex lens gives a virtual image only when the objects lies
a. between principal focus and center of curvature
b. beyond 2 f
c. at the principal focus
d. between principal focus and optical center
Answer- between principal focus and optical center
Que- Magnifying power of simple microscope
a. increase with increase in focal length
b. increase with decrease in focal length
c. no effect with decrease or increase with focal length
d. list distance of distinct vision
Answer- increase with decrease in focal length
Que- Image of an object 5 mm high is only 1 cm high. Magnification produced by lens is
a. 0.5
b. 0.2
c. 1
d. 2
Answer- 2
Que- The least distance of distinct vision for a normal eye is
a. 15 cm
b. 25 cm
c. 30 cm
d. 40 cm
Answer- 25 cm
Que- Least distance of distinct vision
a. increases with increase in age
b. decreases with increase in age
c. neither increases nor decreases
d. becomes infinite after 60 years
Answer- increases with increase in age
Que- If a convex lens of large aperture fails to converge the light rays incident on it to a single point, it is said to suffer from
a. chromatic aberration
b. spherical aberration
c. both spherical and chromatic
d. distortion
Answer- spherical aberration
Que- Two convex lenses of equal focal length f are placed in contact the resultant focal length of the combination is
a. zero
b. focus
c. 2 f
d. f/2
Answer- f/2
Que- A convex lens of focal length f1 and a concave lens of focal length f2 are placed in contact. The focal length of the combination is
a. f2 + f1
b. f2 - f1
c. f1f2/f2+f1
d. f1f2/f1-f2
Answer- f1f2/f1-f2
Que- Final image produced by a compound microscope is
a. real and inverted
b. real and erect
c. virtual and erect
d. virtual and inverted
Answer- virtual and inverted
Que- For normal adjustment, length of astronomical telescope is
a. fo + fe
b. fo - fe
c. fo / fe
d. fe / fo
Answer- fo + fe
Que- In multimode step index fibre the refractive index of core and cladding is
a. same
b. different
c. zero
d. different with refractive index of core higher than cladding
Answer- different with refractive index of core higher than cladding
Que- Dispersional effect may produce error in light signals. This type of error
a. single mode step index fibre
b. multimode step index fibre
c. multimode graded index fibre
d. monomode step index fiber
Answer- multimode graded index fibre
Que- Light signals passes through multimode graded index fibre due to
a. continuous refraction
b. total internal reflection
c. both continuous refraction and total internal reflection
d. diffraction
Answer- continuous refraction
Que- Which one type of fibre is more suitable for transmission of signals in which white light is used ?
a. mono mode step index fibre
b. multi mode step index fibre
c. multi mode graded index fibre
d. single mode step index fibre
Answer- multi mode graded index fibre
Que- Critical angle is that incident angle in denser medium for which angle of refraction is
a. 0 Degree
b. 45 Degree
c. 90 Degree
d. 180 Degree
Answer- 90 Degree
Que- There is no noticeable boundary between core and cladding
a. multi mode step index fibre
b. multi mode graded index fibre
c. single mode step index fibre
d. all types of fibre
Answer- multi mode graded index fibre
Que- The electrical signals change into light signals for transmission through optical fibre. A light pulse represent
a. zero (0)
b. One (1)
c. both zero (0) and one (1)
d. neither zero (0) nor one (1)
Answer- One (1)
Que- A lens, which is thicker at the center and thinner at the edges is called
a. concave lens
b. convex lens
c. plano convex lens
d. plano concave lens
Answer- convex lens
Que- A spectrometer is used to find
a. wave length of light
b. refractive index of the prism
c. wavelength of different colours
d. all of the above
Answer- all of the above
Que- If a convex lens of focal length f is cut into two identical halves along the lens diameter the focal length of each half is
a. f
b. f/2
c. 2f
d. 3f/2
Answer- 2f
Que- A convex and concave lens of focal length f are in contact the focal length of the combinations will be
a. zero
b. f / 2
c. 2f
d. infinite
Answer- infinite
Que- The value of critical angle for glass is
a. 42 Degree
b. 47 Degree
c. 52 Degree
d. 50 Degree
Answer- 42 Degree
Que- In optic fiber transmission system __________ are used regenerate the dim light signal.
a. Diodes
b. Repeaters
c. Laser
d. Transformer
Answer- Repeaters
Que- Magnification of the astronomical telescope is
a. fo+fe
b. fo/fe
c. fe/fo
d. (1+fo/fe)L/fo
Answer- fo/fe
Que- A convex lens acts as a diverging lens if the
a. object is beyond C
b. if the object is with in C
c. if the object is within f
d. both (b) and (c)
Answer- both (b) and (c)
Que- Michelson calculated the speed of light using the instruments
a. spectrometer
b. galvanometer
c. interferometer
d. none of these
Answer- spectrometer
Que- Michelson devised the formula to calculate the speed of light
a. C = 4fd
b. C = 8fd
c. C = 16fd
d. C = 5/2fd
Answer- C = 16fd
Que- The function of collimeter in spectrometer is
a. to produce parallel beams of light
b. to filter the light rays
c. to make them
d. no function
Answer- to produce parallel beams of light
Que- In optic fiber transmission the repeater are separated through a distance of ______ km in newer system.
a. 300km
b. 200km
c. 100km
d. 20km
Answer- 100km
Que- Errors in the transmission of power through optic fiber can be minimized by using a
a. Multimode index fiber
b. Graded index fiber
c. Single mode step index fiber
d. Copper wire
Answer- Graded index fiber
Que- Dimension of pressure is
a. MLT
b. ML-1T-1
c. ML-1T-2
d. ML-2T-2
Answer- ML-1T-2
Que- Temperature is a property which determines
a. How much heat a body contains
b. Whether a body will feel hot or cold to touch
c. In which direction heat will flow between two systems
d. How much total absolute energy a body has
Answer- In which direction heat will flow between two systems
Que- We prefer mercury as a thermometric substance because
a. Over a wide range of temperature its expansion is uniform
b. It does not stick to thermometer glass
c. It opaque to light
d. All of above
Answer- All of above
Que- Numerical value of Boltzmanns constant is
a. 1.38x10-31JK-1
b. 3.18x10-31JK-1
c. 3.18x10-23JK-1
d. 1.38x10-23JK-1
Answer- 1.38x10-23JK-1
Que- In a clinical thermometer the mercury in the capillary tube does not contract once removed from the patient because
a. Mercury takes a long time to contract
b. The amount of mercury use is very small
c. The capillary tube has a small constriction near the bulb
d. The capillary tube is very narrow
Answer- The capillary tube has a small constriction near the bulb
Que- Normal human body temperature 98.6 Degree F corresponds to
a. 37 Degree C
b. 42 Degree C
c. 55 Degree C
d. 410 Degree C
Answer- 37 Degree C
Que- The Fahrenheit and centigrade scales agree to
a. 40
b. 15.5
c. 542
d. 273
Answer- 40
Que- The size of one degree of Celsius is equal to
a. One degree of Fahrenheit scale
b. 1.8 degrees of Fahrenheit scale
c. 3.2 degrees of Fahrenheit scale
d. 2.12 degrees of Fahrenheit scale
Answer- 1.8 degrees of Fahrenheit scale
Que- At constant temperature the graph between V and 1/P is
a. Hyperbola
b. Parabola
c. A curve of any shape
d. A straight lime
Answer- A straight lime
Que- According to Pascals law the pressure of gas in a vessel is
a. Different in different direction
b. Same in all direction
c. Same only along opposite directions
d. Same only along normal directions
Answer- Same in all direction
Que- We can produce heat by
a. Frictional process
b. Chemical processes
c. Electrical processes
d. All of the above
Answer- All of the above
Que- Which one is true for internal energy?
a. It is sum of all forms of energies associated with molecules of a system
b. It is a state function of a system
c. It is proportional to transnational K.E of the molecules
d. All are correct
Answer- All are correct
Que- Metabolism is the name of a process in which energy transformation takes place within
a. Heat engine
b. Human body
c. Atmosphere
d. Laboratory
Answer- Human body
Que- Which one is not an example of adiabatic process ?
a. rapid escape of air from a burst tyre
b. rapid expansion of air
c. conversion of water into ice in refrigerator
d. cloud formation in the atmosphere
Answer- conversion of water into ice in refrigerator
Que- The pressure exerted by a column of mercury 76cm high and at 0 Degree C is called
a. 1 atmosphere
b. 1 Newton per square meter
c. 1 Pascal
d. data is insufficient
Answer- 1 atmosphere
Que- Standard condition STP refer to a gas at
a. 76cm 0 Degree C
b. 760mm 273K
c. 1atm 273K
d. all of the above
Answer- all of the above
Que- If the volume of a gas is held constant and we increase its temperature then
a. its pressure is constant
b. its pressure rises
c. its pressure falls
d. any of above
Answer- its pressure rises
Que- If the pressure of a given gas is held constant its density is inversely proportional to its absolute temperature. We can refer it as another statement of
a. Boyles law
b. Charles law
c. Ideal gas law
d. Avagadros law
Answer- Charles law
Que- Boyles law helds for ideal gases in
a. isochoric processes
b. isobaric processes
c. isothermal processes
d. adiabatic processes
Answer- isothermal processes
Que- Gas molecules of different masses in the same container have the same average transnational kinetic energy which is directly proportional to their
a. volume
b. pressure
c. absolute temperature
d. time
Answer- absolute temperature
Que- The reading on the Fahrenheit scale will be double the reading on the centigrade scale when the temperature on the centigrade scale is
a. 460 Degree C
b. 280 Degree C
c. 360 Degree C
d. 160 Degree C
Answer- 360 Degree C
Que- The area enclosed by the curve ABCDA for a Carnot heat engine represents the work done by Carnot engine
a. at any instant
b. averagely
c. during its operation
d. during one cycle
Answer- during one cycle
Que- For a gas obeying Boyles law if the pressure is doubled the volume becomes
a. double
b. one half
c. four times
d. one fourth
Answer- one half
Que- Triple point of water is
a. 273 Degree C at 6.11 Kpa
b. 273K at 61.6 Kpa
c. 273.16 Degree C at 0.611 Kpa
d. 273.16K at 750 Kpa
Answer- 273.16 Degree C at 0.611 Kpa
Que- Which of the following properties of molecules of a gas is same for all gases at particular temperature?
a. momentum
b. mass
c. velocity
d. kinetic energy
Answer- kinetic energy
Que- Boltzman constant K in terms of universal gas constant R and Avagadros number Na is give as
a. K = RNa
b. K = R/Na
c. K = Na/Ra
d. K = nRNa
Answer- K = R/Na
Que- Average translational kinetic energy per molecule of an ideal gas is given by
a. 3NaT/2R
b. 2NaT/3
c. 3RT/2Na
d. 3Na/2RT
Answer- 3RT/2Na
Que- In which process entropy remains constant
a. isobaric
b. isochoric
c. adiabatic
d. isothermal
Answer- adiabatic
Que- Adiabatic process is also called
a. Heat exchange process
b. Heating process
c. Isentropic process
d. All of the above
Answer- Isentropic process
Que- Which quantity is a state function
a. internal energy
b. heat supply
c. pressure
d. volume
Answer- internal energy
Que- The work done in the isochoric process is
a. constant
b. variable
c. zero
d. depends on situation
Answer- zero
Que- In which process all the heat supplied is converted into work done.
a. isothermal
b. isochoric
c. isobaric
d. isentropic
Answer- isothermal
Que- For the successful operation of Heat engine which condition should be met.
a. cyclic process
b. operated at certain temperature difference
c. both (a) and (b)
d. none of these
Answer- both (a) and (b)
Que- The performance of a refrigerator is described by
a. efficiency
b. coefficient of performance
c. both (a) and (b)
d. not described
Answer- coefficient of performance
Que- The purpose of flywheel in the engines is
a. to smooth out the energy variation
b. to add more weight to engine to work it stable
c. to start engine
d. both (a) and (b)
Answer- to smooth out the energy variation
Que- The unit of entropy is
a. J.K
b. J/K
c. N.m/sec
d. Kgm2/sec2.K
Answer- J/K
Que- Petrol engine is a
a. C.I engine
b. SI engine
c. IC engine
d. all the above
Answer- all the above
Que- When we rub a glass rod with a silk cloth then
a. glass rod acquires negative charge while silk acquires positive charge
b. glass rod acquires positive charge while silk acquires negative charges
c. both glass rod and silk acquire negative charge
d. both glass rod and silk acquire positive charge
Answer- glass rod acquires positive charge while silk acquires negative charges