Question # 1

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

The energy of a photon is represented by

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h/c²

h/T

hc²

hf/c²

The positron was discovered by:

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In cosmic radiation

In 1932

By Carl Anderson

All above

By direc

The photon of radio-waves has energy of about

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1 Me V

1 Ke v

10^-10e v

10¹⁰e v

Which of the following phenomenon proves the particle nature of light

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interference

diffraction

photoelectric effect

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

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

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500°C

900°C

1100°C

1300°C

There is no way to detect:

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Absolute uniform motion

Accelerated motion

State rest

State of motion

None of these

When monochromatic light is allowed to fall on cathode, it begins to emit electrons, these electrons are called

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thermoionic electrons

free electrons

photoelectrons

slow electrons

de-Broglies hypthesis was experimentally verified by

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Maxwell

Compton

Einstein

Davison and Germer

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

A particle having mass and charge equal to that of an electron is called:

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Proton

Positron

Pion

Pi-meson

Both (C) and (D)

If you are moving at relativistic speed between two points that are a fixed distance apart, then the distance between the two points appers

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larger

shorter

equal

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)

In the compton's effect, it is found that the wavelength of incident x-rays is

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greater than the wavelength of scattered x-rays

equal to the wavelength of scattered x-rays

less than the wavelength of scattered x-rays

any one of these

Victor de-Brogile received the Nobel prize in physics in

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1925

1929

1932

1935

0.1 kg mass will be equivalent to the energy

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9 x 10¹⁵J

5 x 10⁸J

6 x 10¹⁶J

9 x 10^-16J

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

When a platinum wire is heated, it appears yellow at

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1600°C

900°C

1100°C

1300°C

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 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

A black body is

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an ideal absorber

an ideal radiator

both of them

none of them

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

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Physical

Chemical

Biological

All of these

None of these

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 symbol to be used in relativity problems denotes:

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Dilated time

Proper time

Life time

Half time

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

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 location and speed anywhere on earth can now be determined using relativistic effects by NAVISTAR to an accuracy of

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2 cm/s

20 cm/s

200 cm/s

2000 cm/s

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 idea of quantization of energy was proposed by:

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Einstein

Max.Planck

Maxwell

Bohr

Rutherford

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

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