1 |
Balmer series was identified in: |
1685
1785
1885
1985
1585
|
2 |
The first series which was identified in the spectrum of hydrogen is called: |
Lyman series
Balmer series
Paschen series
Brackett series
Pfund series
|
3 |
The positron was discovered by: |
In cosmic radiation
In 1932
By Carl Anderson
All above
By direc
|
4 |
A particle having mass and charge equal to that of an electron is called: |
Proton
Positron
Pion
Pi-meson
Both (C) and (D)
|
5 |
Photoelectric effect takes place with a photon of: |
Very high energy
Very low energy
Low energy
High energy
None of these
|
6 |
Compton shift refers to: |
Photon
Meson
Proton
Positron
Both (B) and (D)
|
7 |
The year when A.H. compton was awarded Nobel Prize is: |
1923
1927
1931
1935
None of these
|
8 |
Compton derived an expression to find compton shift by applying to the process, the law of conservation of: |
Energy only
Momentum only
Mass only
Charge only
Both (A) and (B)
|
9 |
Compton studied the scattering of x-rays by loosely bound electrons from: |
NaCl crystal
Graphite crystal
Zirconia
Copper crystal
None of these
|
10 |
The threshold frequency of sodium is 6 x 106MHz. The cut-off wavelength for this metal will be |
500 m
500 nm
500 km
500 cm
None of these
|
11 |
The unit of work function is: |
Joule
Electron volt
That of threshold frequency
Both (A) and (B)
None of these
|
12 |
Photoelectrons are emitted when ultraviolet light falls on: |
Casium
Silver
Potassium
Any of these
None of these
|
13 |
The Nobel Prize on the explanation of photoelectric effect was awarded to: |
Max. Planck
Maxwell
Bohr
Rutherford
None of these
|
14 |
The idea of quantization of energy was proposed by: |
Einstein
Max.Planck
Maxwell
Bohr
Rutherford
|
15 |
Intensity of light determines the: |
Energy of each photon
Number of photons
Speed of photons
Size of photons
None of these
|
16 |
Electromagnetic -radiation means: |
Photons
protons
Electrons
Mesons
None of these
|
17 |
The way through which electromagnetic radiations or photons interact with matter depends upon their: |
Wavelength
Frequency
Energy
Temperature
All of these
|
18 |
If A represents linear momentum and c, the velocity of light, then unit of pc in international system of units is: |
Newton
Joule
Joule-Sec
Joule-s<sup>-1</sup>
Watt
|
19 |
Max Planck received the Nobel Prize for his discovery of energy quants in: |
1718 AD
1918 AH
1818 AD
1918 AD
None of these
|
20 |
The ratio of energy E to the corresponding frequency (f) of the radiation (emitted or absorbed) is called: |
Wien's constant
Stefen's constnat
Planck's constant
Boltzmann's constant
None of these
|
21 |
Wien's constant is measured in: |
Metre per kelviin
Metre kelvin
Kelvin per meter
Joules
Dynes
|
22 |
The intensity of emitted energy (with wavelength) radiated from a black body at different temperatures was initially measured by: |
Lummer
Planck
Pringsheim
Both (A ) and (B)
Both (A) and (C)
|
23 |
When platinum wire is heated, then at the temperature of 500 oC, it becomes: |
Yellow
Orange red
Dull red
White
Cherry red
|
24 |
The nature of radiations emitted by a hot body depends upon its: |
Metarial
Temperature
colour
Volume
Length
|
25 |
When the atomic particle are moving with velocities approaching that of light: |
Newton's laws become valid
Relativistic effects become prominent
Botha(A) and (B) are valid
Neither (A)nor (B)
There mass becomes zero.
|
26 |
As compared to the distance measured by an observer on Earth, the distance from Earth to a star measured by an observer in a moving spaceship would seem: |
Smaller
Lerger
Same
Much larger
None of these
|
27 |
the dilation of time applies to the timing processes which are: |
Physical
Chemical
Biological
All of these
None of these
|
28 |
Due to relative motion of observer and the frame of reference of events, time always: |
Dilates itself
Contracts itself
Stretches itself
Both (A) and (C)
None of these
|
29 |
Practically the quantity v/c is always: |
less than one
Equal to one
Greater then one
all of these
None of these
|
30 |
the symbol to be used in relativity problems denotes: |
Dilated time
Proper time
Life time
Half time
None of these
|