Question # 1

The concept of direction and position are purely

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absolute

relative

absolute or relative

none of these

Converse of pair production is known as

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Compton effect

annihilation of matter

photoelectric effect

none of these

Wave nature of particle was proposed by

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Einstein

Plank

De-Brogile

Max well

The analysis of the distribution of wavelengths of the radiation emitted from a hot body set the foundation of new mechanics, known as

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classical mechanics

Newtonian mechanics

quantum mechanics

statistical mechanics

The whole shape of the black body spectrum for all wavelengths was explained by the formula proposed by

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Max plank

Newton

Einstein

J.J. Thomson

S.I. unit of planks constant is

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J-s^-1

J.s

J.s^-2

J.s²

the symbol to be used in relativity problems denotes:

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Dilated time

Proper time

Life time

Half time

None of these

Newton's law of motion do not hold in

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an accelerated frame of reference

an unaccelerated frame of reference

both of these

none of these

The Nobel Prize on the explanation of photoelectric effect was awarded to:

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Max. Planck

Maxwell

Bohr

Rutherford

None of these

According to the special theory of relativity, a moving clock

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runs faster

runs slower

neither runs faster nor slower

all of these

The stopping voltage for a certain metal is 100 volts, then the work function for the cathode plate is

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100 J

1.6 x 10^-17J

100 eV

1.6 x 10^-17eV

The idea of quantization of energy was proposed by:

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Einstein

Max.Planck

Maxwell

Bohr

Rutherford

Electromagnetic radiation or photons interact with matter in

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two distinct ways

three distinct ways

four distinct ways

five distinct ways

A particle of mass 5.0 mg moves with a speed of 8.0 m/s. Its de-Brogile wavelength is

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1.66 m

1.66 x 10^-10m

1.66 x 10^-29cm

1.66 x 10^-29m

A non-inertial frame of reference is one, in which

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law of inertial is valid

all laws of physics are the same in all frames

a>0 or a<0

a=0

The special theory of relativity treats problems invoving

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inertial frame of references

accelerating frame of references

both of these

none of these

The Einstein's changes in length, mass and time are not observed in common life because

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We dont observer then seriously

The masses are too large

Their speed is too small than the speed of right

All of the above

According to Einstein, with the great increase in the speed of the body the relativistic length of the body

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Remains constant

Decreases

Increases

Reduces to zero

When a platinum wire is heated, it appears orange red at

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500°C

900°C

1100°C

1300°C

A high temperature, the proportion of shorter wavelengths radiation, emitted by the body

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decreases

first increases then decreases

increases

any one of them

The energy of the 4th orbit in hydrogen atom is

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2.5 ev

- 3.5 ev

-0.85 ev

-13.6 ev

When a position comes close to an electron they annihilate into

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one photon

two photons which travel in the same direction

two photons which travels in the opposite direction

two photons which travel in any direction

With the help of 50 K v electron microscope, a resolution of

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0.5 to 1 m to possible

1 m to 10 m is possible

0.5 to 1 nm is possible

1 to 10 nm is possible

A black body is

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an ideal absorber

an ideal radiator

both of them

none of them

Due to relative motion of observer and the frame of reference of events, time always:

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Dilates itself

Contracts itself

Stretches itself

Both (A) and (C)

None of these

If a body reaches a speed equal to the speed of light, then its mass will became

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zero

very small

infinity

none of these

The value of the plank's constant 'h' is given by

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1.6 x 10^-19J

1.67 x 10^-27Kg

6.63 x 10³⁴Js

6.63 x 10^-34Js

Photoelectric effect takes place with a photon of:

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Very high energy

Very low energy

Low energy

High energy

None of these

Wien's constant is measured in:

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Metre per kelviin

Metre kelvin

Kelvin per meter

Joules

Dynes

The value of threshold frequency for different metals is

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different

same

may be different or may be same

none of these

When a position comes close to an electron they annihilate into photons such that

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each photon has energy 0.51 Me v

each photon has energy 1.02 Me v

each photon has energy 0.25 Me v

none of these

When a platinum wire is heated, it appears yellow at

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1600°C

900°C

1100°C

1300°C

G.P. Thomson observer experimentally that electrons and neutrons possess

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particle-like properties

wave-like properties

neither particle nor wave like properties

none of these

Max Planck received the Nobel Prize for his discovery of energy quants in:

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1718 AD

1918 AH

1818 AD

1918 AD

None of these

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