Question # 1

Position was discovered by Carl Anderson in

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1920

1925

1928

1932

When a platinum wire is heated, it appears orange red at

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500°C

900°C

1100°C

1300°C

the symbol to be used in relativity problems denotes:

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Dilated time

Proper time

Life time

Half time

None of these

The existence of position was predicted by Dirace in

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1920

1925

1930

1928

Current, voltage, resistance measuring circuit is connected with the galvanometer with the help of switch, known as

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ON switch

off switch

function switch

none of these

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 Max plank, energy is redialed or absorbed in

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discrete packets

continuous waves

either of them

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

In order to produce pair production, a photon must have a energy

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0.511 Me v

0.256 Me v

1.02 Me v

0.956 Me v

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

Due to relative motion of observer and the frame of reference of events, time always:

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Dilates itself

Contracts itself

Stretches itself

Both (A) and (C)

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

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 positron was discovered by:

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In cosmic radiation

In 1932

By Carl Anderson

All above

By direc

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 length contraction happens only

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Opposite to the direction of motion

along the direction of motion

perpendicular to the direction of motion

In any direction

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