Question # 1

The idea of quantization of energy was proposed by:

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Einstein

Max.Planck

Maxwell

Bohr

Rutherford

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

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

At the temperature, a body emits radiation which is principally

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of long wavelengths in the visible region

of long wavelengths in the invisible infrared region

of short wavelength in invisible ultraviolet region

none of these

Momentum is a parameter associated with

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wave motion

particle motion

neither wave nor particle motion

none of these

The Einstein's changes in length, mass and time are not observed in common life because

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We dont observer then seriously

The masses are too large

Their speed is too small than the speed of right

All of the above

de-Broglies hypthesis was experimentally verified by

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Maxwell

Compton

Einstein

Davison and Germer

The special theory of relativity is based on the

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one postulate

two postulates

three postulates

four postulates

The concept of direction and position are purely

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absolute

relative

absolute or relative

none of these

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)

When a platinum wire is heated, it appears white at

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1600°C

900°C

1100°C

1300°C

The unit of work function is:

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Joule

Electron volt

That of threshold frequency

Both (A) and (B)

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

Which one of the following physical quantities changes with relativistic speed

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Length

Mass

Time

All of the above

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

The value of threshold frequency for different metals is

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different

same

may be different or may be same

none of these

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