Question # 1

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 photon of radio-waves has energy of about

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1 Me V

1 Ke v

10^-10e v

10¹⁰e v

There is certain frequency below which no electrons are emitted from the metal surface, this frequency is known as

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maximum frequency

minimum frequency

threshold frequency

all of these

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

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

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1916

1919

1921

1923

Position and momentum of a particle cannot both be measured simultaneously with perfect accuracy. This is the statement of

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photoelectric effect

pair production

Compton effect

uncertainty principle

Which of the following is not an example of intertial frame

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a body placed on the surface of earth

a body placed in a car moving with uniform velocity

a body placed in a car moving with same acceleration

none of these

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

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

The way through which electromagnetic radiations or photons interact with matter depends upon their:

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Wavelength

Frequency

Energy

Temperature

All of these

In photoelectric effect the energy of ejected electrons depend on

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The frequency

The intensity

Both frequency and intensity

None of these

The positron was discovered by:

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In cosmic radiation

In 1932

By Carl Anderson

All above

By direc

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

Pair production is the phenomenon in which

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matter is converted into energy

energy is converted into matter

light is converted into electrical energy

electrical energy is converted into light

When low energy photon interact with a metal,which of the following effect is likely to be taken place

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pair production

photoelectric

Compton effect

None of these

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

Compton was awarded Nobel prize in physics in

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1921

1923

1925

1927

Position was discovered by Carl Anderson in

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1920

1925

1928

1932

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

Photoelectrons are emitted when ultraviolet light falls on:

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Casium

Silver

Potassium

Any of these

None of these

When a high energy photon interact with a metal, which of the following effect is most likely to be taken place

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pair production

photoelectric effect

Compton effect

None of these

The mass of an object will be doubled at speed

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1.6 x 10⁸ms^-1

2.6 X 10⁸ms^-1

2.6 x 10⁷ms^-1

2.6 x 10⁹ms^-1

According to the Max plank, energy is redialed or absorbed in

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discrete packets

continuous waves

either of them

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

The concept of direction and position are purely

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absolute

relative

absolute or relative

none of these

In order to produce pair production, a photon must have a energy

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0.511 Me v

0.256 Me v

1.02 Me v

0.956 Me v

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 intensity of emitted energy (with wavelength) radiated from a black body at different temperatures was initially measured by:

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Lummer

Planck

Pringsheim

Both (A ) and (B)

Both (A) and (C)

If the radius of first orbit of hydrogen atom is 0.53° A the radius of second orbit will be

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2.120°A

0.212°A

21.2°A

0.14°

a

Converse of pair production is known as

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Compton effect

annihilation of matter

photoelectric effect

none of these

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