Question # 1

Compton derived an expression to find compton shift by applying to the process, the law of conservation of:

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Energy only

Momentum only

Mass only

Charge only

Both (A) and (B)

The analysis of the distribution of wavelengths of the radiation emitted from a hot body set the foundation of new mechanics, known as

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classical mechanics

Newtonian mechanics

quantum mechanics

statistical mechanics

According to the special theory of relativity, a moving clock

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runs faster

runs slower

neither runs faster nor slower

all of these

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

the symbol to be used in relativity problems denotes:

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Dilated time

Proper time

Life time

Half time

None of these

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

The speed of a pendulum is measured to be 3.0 s in the inertial reference frame of the pendulum. What is its period measured by an observer moving at a speed of 0.95 c with respect to the pendulum

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2.9 s

3.0 s

6.6 s

9.6 s

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

The location and speed anywhere on earth can now be determined using relativistic effects by NAVISTAR to an accuracy of

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2 cm/s

20 cm/s

200 cm/s

2000 cm/s

The ratio of energy E to the corresponding frequency (f) of the radiation (emitted or absorbed) is called:

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Wien's constant

Stefen's constnat

Planck's constant

Boltzmann's constant

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 photon of radio-waves has energy of about

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1 Me V

1 Ke v

10^-10e v

10¹⁰e v

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

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

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 high energy photon interact with a metal, which of the following effect is most likely to be taken place

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pair production

photoelectric effect

Compton effect

None of these

Compton studied the scattering of x-rays by loosely bound electrons from:

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NaCl crystal

Graphite crystal

Zirconia

Copper crystal

None of these

As the light shines on the metal surface, the electrons are ejected

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slowly

instantaneously

either of these

none of these

The concept of direction and position are purely

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absolute

relative

absolute or relative

none of these

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

Absolute motion cannot be detected

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in its own frame of references

in a different frame of references

both in its frame and different frame of references

none of these

An electron is accelerated through a potential difference of 50v. its de-Brogile wavelength is

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1.66 x 10^-29m

1.74 x 10^-10cm

17.4 x 10^-6m

1.74 x 10^-10m

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

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1916

1919

1921

1923

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

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.

The idea of quantization of energy was proposed by:

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Einstein

Max.Planck

Maxwell

Bohr

Rutherford

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

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1900

1906

1912

1918

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

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

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