Paper for Entry Test Preparation
Physics 2nd year Chapter No. 19
Total marks:- 160 Time
allowed 25 minutes
Note:- Fill
the appropriate answer of the following questions in the answer sheet. Double
filling and erasing is not allowed. Each question carries equal marks and for
each wrong answer minus one is awarded.
1) A body at rest remains at rest unless:
a)
A balanced force produced motion in it b)
An unbalanced force produces acceleration in it
c)
An unbalanced force does not produce acceleration in it d) A balanced force produces acceleration in it
2) The special theory of relativity treats the
problems involving:
a)
Inertial frames of references b)
Non-inertial frames
c)
Non-accelerated frames d)
Both (a) and (c)
3) The special theory of relativity is based on:
a)
Four postulates b)
Three postulates c) Two
postulates d) One
postulate
4) The symbol to be used in relativity problems
denotes:
a)
Dilated time b)
Proper time c)
Life time d)
Half life
5) Due to relative motion of observer and the frame
of reference of events, time always:
a)
Dilates itself b)
Contracts itself c)
Stretches itself d)
Both (a) and (c)
6) Mass of an objet:
a)
Is a varying quantity b)
Depends upon the speed of object
c)
Indicates its inertia d)
All of above
7) According to special theory of relativity, mass
and energy are:
a)
Different entities b)
Related as E = mc2 c)
Inter convertible d) Similar
entities
8) The nature of radiation emitted by a hot body
depends upon its:
a)
Material b)
Temperature c)
Colour d)
Volume
9) At high temperature, the hot body emits
radiations of:
a)
High energy b)
Longer wavelength c) Shorter
wavelength d) Both (a) and (c)
10) When platinum wire is heated, then at the
temperature of 500oC, it becomes:
a)
Yellow b)
Orange red c)
Dull red d)
White
11) Black colour is:
a)
A good absorber of heat b) A bad
absorber of heat c) A good
reflector of heat d) Non of all
12) Wien’s constant is measured in:
a)
Metre per Kelvin b) Meter
Kelvin c) Kelvin per
meter d) Joules
13) Plank suggested that energy is radiated or
absorbed:
a)
In discrete packets b) As
continuous wave c) Mixture of
(a) and (b) d) Any of these
14) The detection of r-radiation with energy ~ 1MeV
as quanta is:
a)
Not possible b)
Possible by radiation detector
c)
Is possible by counter d)
Possible with open eye
15) Electromagnetic radiation means:
a)
Photons b)
Protons c)
Electrons d)
Mesons
16) The process through which photons can interact
with matter is:
a)
Photoelectric effect b)
Compton effect c) Pair
production d) Any of
these
17) If the photoelectric current goes on decreasing,
it means that:
a)
Photons are attracted by the anode b)
Photoelectrons are repelled by the anode
c)
Photoelectrons are attracted by the anode d)
Photons are repelled by the anode
18) The amount of photoelectric current depends
upon:
a)
Energy of incident photons b)
Intensity of light beam
c)
Both (a) and (b) d)
Magnitude of stopping potential
19) The maximum energy of photoelectrons depends on:
a)
Nature of metal surface b)
Frequency of incident light
c)
Intensity of incident light d)
Both (b) and (c)
20) The classical electromagnetic wave theory of
light cannot explain:
a)
Difference b/w intensity and energy b)
Threshold frequency of light
c)
Instantaneous emission of photoelectrons d)
Any of these
21) Photoelectrons are emitted when visible light
falls on:
a)
Sodium b)
Caesium coated oxidized silver
c)
Potassium d)
Both (a) and (c)
22) A photocell can be used o operate:
a)
Security systems b)
Counting system c)
Automatic door system d) All of
these
23) Photoelectrons are emitted when ultraviolet
light falls on:
a)
Caesium b)
Silver c)
Potassium d)
Any of these
24) A. H. Compton studied scattering of X-rays by:
a)
Loosely bound electrons b) Tightly
bound electrons c) Tightly bound
protons d) Loosely
bound photons
25) Compton derived an expression to find Compton
shift by applying to the process, the law of conversation of:
a)
Energy only b)
Momentum only c) Mass only d) Both (a) and (b)
26) Compton shift is actually the change in:
a)
Wavelength of incident photon b)
Mass of incident photon
c)
Mass of loosely bound electron d)
Total charge
27) Quasi-free electron means:
a)
Tightly bound electrons b) Loosely
bound electrons c) Completely free
electrons d) Non of all
28) Photoelectric effect takes place with a photon
of:
a)
High energy b) Low
energy c) Very
high energy d) Very low
energy
29) Radiant energy is converted into matter in case
of:
a)
Photoelectric effect b) Pair
production c) Compton
effect d) Annihilation
of matter
30) Pair production if also called:
a)
Energy production b) Charge
production c) Materialization
of energy d) Matter
change
into energy
31) Every particle has a corresponding antiparticle
with:
a)
The same mass b)
Different mass c)
Opposite charge d) Same
energy
32) While the matter annihilates, the two photons
travel in opposite directions so that:
a)
Momentum is conserved b)
Charge in conserved
c)
Angular momentum is conserved d)
Total mass is conserved
33) Prince de Broglie was awarded Noble prize for
his work on:
a)
Photoelectric effect b)
Pair production
c)
Dual nature of particle d)
Experimental verification of wave nature of particle
34) Wave nature of light was confirmed by:
a)
Photoelectric effect b)
Interference c)
Diffraction d)
Both (b) and (c)
35) The basic concept used in the construction of an
electron microscope is:
a)
Particle nature of wave b) Waves
nature of particles c) Both (a) and (b) d) Non of all
36) In electron microscope, we sue:
a)
Optical lenses b)
Electric field c)
Magnetic fields d) Both
(b) and (c)
37) The magnetic conducting lens concentrates the
electrons beam for:
a)
Specimen to electron gun b) Electron
gun to specimen c) Specimen to screen d) Electron gun to screen
38) Uncertainty in a measurement due to wave
particle duality is:
a)
Prominent for microscope particles b)
Prominent for macroscopic particles
c)
Negligible for macroscopic particles d)
Both (a) and (b)
39) We must use light of short wavelength in order
to observe the position of the electron:
a)
With less uncertainty b)
With minimized diffraction effect
c)
With maximum uncertainty d)
Both (a) and (b)
40) At the most, the photon of light can transfer
all its momentum to the micro particle which amount to:
a)
λ / h b)
h / λ c)
h λ d)
h + λ
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment