Question # 1

Electromagnetic -radiation means:

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Photons

protons

Electrons

Mesons

None of these

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

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

When a platinum wire is heated, it appears dull red at about

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500°C

900°C

1100°C

1300°C

The general theory of relativity treats problems involving

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inertial frame of references

accelerating frame of references

both of these

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

When a platinum wire is heated, it appears white at

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1600°C

900°C

1100°C

1300°C

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

A particle of mass 5.0 mg moves with a speed of 8.0 m/s. Its de-Brogile wavelength is

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1.66 m

1.66 x 10^-10m

1.66 x 10^-29cm

1.66 x 10^-29m

Compton was awarded Nobel prize in physics in

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1921

1923

1925

1927

A black body is

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an ideal absorber

an ideal radiator

both of them

none of them

The inside cavity of the black body is

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painted white

painted silver

blackened with soot

painted red

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

The special theory of relativity is based on the

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one postulate

two postulates

three postulates

four postulates

According to Einstein, with the great increase in the speed of the body the relativistic length of the body

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Remains constant

Decreases

Increases

Reduces to zero

Compton derived an expression to find compton shift by applying to the process, the law of conservation of:

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Energy only

Momentum only

Mass only

Charge only

Both (A) and (B)

The energy of a photon is represented by

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h/c²

h/T

hc²

hf/c²

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

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

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