Question # 1

At the temperature, a body emits radiation which is principally

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of long wavelengths in the visible region

of long wavelengths in the invisible infrared region

of short wavelength in invisible ultraviolet region

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)

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

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momentum

charge

energy

mass

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

Victor de-Brogile received the Nobel prize in physics in

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1925

1929

1932

1935

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

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

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

Electromagnetic radiation or photons interact with matter in

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two distinct ways

three distinct ways

four distinct ways

five distinct ways

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 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

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

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)

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

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