Question # 1

The energy of photon 'E' is proported to

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The magnetic field H

The electric field E

Both the electric and magnetic field H and E

Frequency

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

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

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

Strictly speaking, the earth is:

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An accelerated frame of reference

A non-inertial frame of reference

An inertial frame of reference

^{A non-accelerated frame of reference}

Both (A) and (B)

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

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

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

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momentum

charge

energy

mass

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

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

Newton's law of motion do not hold in

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an accelerated frame of reference

an unaccelerated frame of reference

both of these

none of these

When platinum wire is heated, it appears cherry red at

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1600°C

900°C

1100°C

1300°C

The whole shape of the black body spectrum for all wavelengths was explained by the formula proposed by

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Max plank

Newton

Einstein

J.J. Thomson

An inertial frame is that frame in which

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a>0

a=0

a<0

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

The nature of radiations emitted by a hot body depends upon its:

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Metarial

Temperature

colour

Volume

Length

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