Question # 1

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

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momentum

charge

energy

mass

An inertial frame is that frame in which

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a>0

a=0

a<0

none of these

When a position comes close to an electron they annihilate into

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one photon

two photons which travel in the same direction

two photons which travels in the opposite direction

two photons which travel in any direction

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

When a platinum wire is heated, it appears white at

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1600°C

900°C

1100°C

1300°C

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

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

The energy of a photon is represented by

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h/c²

h/T

hc²

hf/c²

Which one of the following physical quantities changes with relativistic speed

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Length

Mass

Time

All of the above

Wave nature of particle was proposed by

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Einstein

Plank

De-Brogile

Max well

A photon is considered to have

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Momentum

Energy

Wavelength

All of the above

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

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1900

1906

1912

1918

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

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

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)

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

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