Question # 1

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

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 special theory of relativity treats problems invoving

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inertial frame of references

accelerating frame of references

both of these

none of these

A bar 1.0 m in length and located along x-axix moves with a speed of 0.75 c with respect to a stationary observer. The length of the bar as measured by the stationary observer is

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1.66 m

1.0 m

0.66 m

2.66 m

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

The special theory of relatively treats the problems involving:

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Inertial frames of reference

Non-inertial frames

Non-accelerated frame

Botha (A) and (C)

Both (B) and (C)

The way through which electromagnetic radiations or photons interact with matter depends upon their:

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Wavelength

Frequency

Energy

Temperature

All of these

In photoelectric effect the energy of ejected electrons depend on

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The frequency

The intensity

Both frequency and intensity

None of these

The concept of direction and position are purely

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absolute

relative

absolute or relative

none of these

The special theory of relativity is based on:

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Four postulates

Three postulates

Two postulates

One postulate

None of these

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)

The Nobel Prize on the explanation of photoelectric effect was awarded to:

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Max. Planck

Maxwell

Bohr

Rutherford

None of these

The energy of the 4th orbit in hydrogen atom is

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2.5 ev

- 3.5 ev

-0.85 ev

-13.6 ev

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

The photoelectric effect, the maximum energy of photoelectrons depends on the

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particular metal surface

frequency of incident light

both of them

none of them

A photon is considered to have

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Momentum

Energy

Wavelength

All of the above

Photoelectric effect takes place with a photon of:

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Very high energy

Very low energy

Low energy

High energy

None of these

Davision and Germer performed experiment to verify

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de-Brogile hypothesis

theory of relativity

Newton's law of gravitation

Mass-energy relation

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

Photocell is a device which converts

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chemical energy into electrical energy

electrical energy into light energy

heat energy into electrical energy

light energy into electrical energy

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

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momentum

charge

energy

mass

From the theory of relativity, momentum p of the photon is related to energy as

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p = hfc

p = hf/c

p = f(hc,f)

p = cf/h

Compton was awarded Nobel prize in physics in

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1921

1923

1925

1927

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

There is no way to detect:

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Absolute uniform motion

Accelerated motion

State rest

State of motion

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)

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

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Metarial

Temperature

colour

Volume

Length

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

The inside cavity of the black body is

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painted white

painted silver

blackened with soot

painted red

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

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

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

Max Planck received the Nobel Prize for his discovery of energy quants in:

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1718 AD

1918 AH

1818 AD

1918 AD

None of these

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

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