Question # 1

As compared to the distance measured by an observer on Earth, the distance from Earth to a star measured by an observer in a moving spaceship would seem:

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Smaller

Lerger

Same

Much larger

None of these

Which of the following is not an example of intertial frame

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a body placed on the surface of earth

a body placed in a car moving with uniform velocity

a body placed in a car moving with same acceleration

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

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

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 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

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

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 special theory of relativity is based on:

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Four postulates

Three postulates

Two postulates

One postulate

None of these

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

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

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500°C

900°C

1100°C

1300°C

Compton shift refers to:

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Photon

Meson

Proton

Positron

Both (B) and (D)

The Stephen-Boltzmann law for the black body radiation is given by

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E = T²

E = -T²

E = T⁴

E = -T⁴

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 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

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 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 positron was discovered by:

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In cosmic radiation

In 1932

By Carl Anderson

All above

By direc

An intertial frame of reference is a frame of reference which is

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at rest

moving with uniform velocity

either at rest or moving with uniform velocity

none of these

When platinum wire is heated, then at the temperature of 500 ^oC, it becomes:

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Yellow

Orange red

Dull red

White

Cherry red

Which of the following phenomenon proves the particle nature of light

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interference

diffraction

photoelectric effect

none of these

There is no way to detect:

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Absolute uniform motion

Accelerated motion

State rest

State of motion

None of these

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)

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

G.P. Thomson observer experimentally that electrons and neutrons possess

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particle-like properties

wave-like properties

neither particle nor wave like properties

none of these

The concept of direction is purely:

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Absolute

Relative

Relative to stars always

Relative to the sun always

None of these

The year when A.H. compton was awarded Nobel Prize is:

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1923

1927

1931

1935

None of these

The idea of quantization of energy was proposed by:

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Einstein

Max.Planck

Maxwell

Bohr

Rutherford

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

When a platinum wire is heated, it appears white at

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1600°C

900°C

1100°C

1300°C

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

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

The threshold frequency of sodium is 6 x 10⁶MHz. The cut-off wavelength for this metal will be

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500 m

500 nm

500 km

500 cm

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

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