Question # 1

According to the electromagnetic wave theory of light, increasing the intensity of incident light should increase the

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number of photoelectrons

size of the photoelectrons

charge on photoelectrons

K.E of photoelectrons

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 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 year when A.H. compton was awarded Nobel Prize is:

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1923

1927

1931

1935

None of these

The energy of a photon in a beam of infrared radiation of wavelength 1240 nm is

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100 ev

10⁶e v

10³e v

1.0 e v

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

Photocell is a device which converts

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chemical energy into electrical energy

electrical energy into light energy

heat energy into electrical energy

light energy into electrical energy

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

Davision and Germer performed experiment to verify

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de-Brogile hypothesis

theory of relativity

Newton's law of gravitation

Mass-energy relation

Which of the following phenomenon proves the particle nature of light

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interference

diffraction

photoelectric effect

none of these

When platinum wire is heated, it appears cherry red at

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1600°C

900°C

1100°C

1300°C

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

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

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

The idea of quantization of energy was proposed by:

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Einstein

Max.Planck

Maxwell

Bohr

Rutherford

According to the special theory of relativity, time is

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absolute quantity

not absolute quantity

constant quantity

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

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

In process of annihilation of matter, the two photons produced move in opposite direction to converse

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momentum

charge

energy

mass

The special theory of relativity is based on:

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Four postulates

Three postulates

Two postulates

One postulate

None of these

The photon of radio-waves has energy of about

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1 Me V

1 Ke v

10^-10e v

10¹⁰e v

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 a platinum wire is heated, it appears orange red at

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500°C

900°C

1100°C

1300°C

the dilation of time applies to the timing processes which are:

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Physical

Chemical

Biological

All of these

None of these

The concept of direction is purely:

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Absolute

Relative

Relative to stars always

Relative to the sun always

None of these

Photoelectrons are emitted when ultraviolet light falls on:

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Casium

Silver

Potassium

Any of these

None of these

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

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

The unit of work function is:

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Joule

Electron volt

That of threshold frequency

Both (A) and (B)

None of these

Wave nature of particle was proposed by

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Einstein

Plank

De-Brogile

Max well

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

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

There is no way to detect:

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Absolute uniform motion

Accelerated motion

State rest

State of motion

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

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