Question # 1

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

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 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 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)

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 value of threshold frequency for different metals is

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different

same

may be different or may be same

none of these

Position was discovered by Carl Anderson in

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1920

1925

1928

1932

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

Max plank received the Nobel Prize in physics for his discovery of energy quanta in

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1900

1906

1912

1918

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 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

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

The Stephen-Boltzmann law for the black body radiation is given by

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E = T²

E = -T²

E = T⁴

E = -T⁴

The inside cavity of the black body is

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painted white

painted silver

blackened with soot

painted red

Intensity of light determines the:

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Energy of each photon

Number of photons

Speed of photons

Size of photons

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

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