Question # 1

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

With the help of 50 K v electron microscope, a resolution of

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0.5 to 1 m to possible

1 m to 10 m is possible

0.5 to 1 nm is possible

1 to 10 nm is possible

In order to produce pair production, a photon must have a energy

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0.511 Me v

0.256 Me v

1.02 Me v

0.956 Me v

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 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)

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

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500°C

900°C

1100°C

1300°C

S.I. unit of planks constant is

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J-s^-1

J.s

J.s^-2

J.s²

When a platinum wire is heated, it appears dull red at about

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500°C

900°C

1100°C

1300°C

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 mass of an object will be doubled at speed

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1.6 x 10⁸ms^-1

2.6 X 10⁸ms^-1

2.6 x 10⁷ms^-1

2.6 x 10⁹ms^-1

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 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

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

According to the de-Brogile relation, an object of large mass and ordinary speed has

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very small wavelength

very large wavelength

very small frequency

all of these

A black body is

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an ideal absorber

an ideal radiator

both of them

none of them

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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