Question # 1

Compton derived an expression to find compton shift by applying to the process, the law of conservation of:

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Energy only

Momentum only

Mass only

Charge only

Both (A) and (B)

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

The ratio of energy E to the corresponding frequency (f) of the radiation (emitted or absorbed) is called:

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Wien's constant

Stefen's constnat

Planck's constant

Boltzmann's constant

None of these

Strictly speaking, the earth is:

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An accelerated frame of reference

A non-inertial frame of reference

An inertial frame of reference

^{A non-accelerated frame of reference}

Both (A) and (B)

The emission of electrons from a metal surface when exposed to light of suitable frequency is called the

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pair production

Compton effect

photoelectric effect

relativity

When a platinum wire is heated, it appears yellow at

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1600°C

900°C

1100°C

1300°C

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

Electromagnetic radiation or photons interact with matter in

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two distinct ways

three distinct ways

four distinct ways

five distinct ways

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

The positron was discovered by:

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In cosmic radiation

In 1932

By Carl Anderson

All above

By direc

When the atomic particle are moving with velocities approaching that of light:

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Newton's laws become valid

Relativistic effects become prominent

Botha(A) and (B) are valid

Neither (A)nor (B)

There mass becomes zero.

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 length contraction happens only

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Opposite to the direction of motion

along the direction of motion

perpendicular to the direction of motion

In any direction

Albert Einstein got the Nobel prize in physics for his explanation of photoelectric effect in

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1916

1919

1921

1923

The photoelectric effect, the maximum energy of photoelectrons depends on the

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particular metal surface

frequency of incident light

both of them

none of them

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

Current, voltage, resistance measuring circuit is connected with the galvanometer with the help of switch, known as

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ON switch

off switch

function switch

none of these

Absolute motion cannot be detected

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in its own frame of references

in a different frame of references

both in its frame and different frame of references

none of these

Max plank founded a mathematical model resulting in an equation that describes the shape of observed black body radiation curves exactly, in

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1890

1895

1900

1905

According to the de-Brogile relation, an object of large mass and ordinary speed has

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very small wavelength

very large wavelength

very small frequency

all of these

An intertial frame of reference is a frame of reference which is

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at rest

moving with uniform velocity

either at rest or moving with uniform velocity

none of these

According to the special theory of relativity

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mass and energy are same entities

mass and energy are same entities but interconverible

mass and energy are different entities but interconverible

mass and energy are different entities but non-interconveritble

The mass 'm' of a body moving at 0.8 c (whose rest mass is mo) becomes

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2 mo

1.67 mo

0.67 mo

2.67 mo

Practically the quantity v/c is always:

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less than one

Equal to one

Greater then one

all of these

None of these

the symbol to be used in relativity problems denotes:

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Dilated time

Proper time

Life time

Half time

None of these

If a material object moves with the speed of light 'C' its mass becomes

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Equal to its rest mass

Four times of its rest mass

Double of its rest mass

Infinite

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

The value of the Stephen's constant for black body radiations is given by

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5.6 x 10⁸Wm^-2K^-4

5.67 x 10^-8Wm^-2K^-4

2.9 x 10^-3mK

2.9 x 10³mK

The concept of direction is purely:

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Absolute

Relative

Relative to stars always

Relative to the sun always

None of these

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

An electron is accelerated through a potential difference of 50v. its de-Brogile wavelength is

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1.66 x 10^-29m

1.74 x 10^-10cm

17.4 x 10^-6m

1.74 x 10^-10m

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