Question # 1

When platinum wire is heated, then at the temperature of 500 ^oC, it becomes:

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Yellow

Orange red

Dull red

White

Cherry red

Wave nature of particle was proposed by

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Einstein

Plank

De-Brogile

Max well

The existence of position was predicted by Dirace in

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1920

1925

1930

1928

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

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Physical

Chemical

Biological

All of these

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

An inertial frame is that frame in which

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a>0

a=0

a<0

none of these

de-Broglies hypthesis was experimentally verified by

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Maxwell

Compton

Einstein

Davison and Germer

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

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 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 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)

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

Practically the quantity v/c is always:

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less than one

Equal to one

Greater then one

all of these

None of these

Albert Einstein got the Nobel prize in physics for his explanation of photoelectric effect in

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1916

1919

1921

1923

An intertial frame of reference is a frame of reference which is

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at rest

moving with uniform velocity

either at rest or moving with uniform velocity

none of these

There is no way to detect:

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Absolute uniform motion

Accelerated motion

State rest

State of motion

None of these

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

The positron was discovered by:

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In cosmic radiation

In 1932

By Carl Anderson

All above

By direc

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

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

Which one of the following physical quantities changes with relativistic speed

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Length

Mass

Time

All of the above

A photon is considered to have

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Momentum

Energy

Wavelength

All of the above

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

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

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Remains constant

Decreases

Increases to infinity

Reduced to zero

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

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

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500°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

Electromagnetic -radiation means:

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Photons

protons

Electrons

Mesons

None of these

When a platinum wire is heated, it appears white 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

When the atomic particle are moving with velocities approaching that of light:

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Newton's laws become valid

Relativistic effects become prominent

Botha(A) and (B) are valid

Neither (A)nor (B)

There mass becomes zero.

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