Question # 1

A particle having mass and charge equal to that of an electron is called:

Choose an answer

Proton

Positron

Pion

Pi-meson

Both (C) and (D)

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

Choose an answer

1.66 x 10^-29m

1.74 x 10^-10cm

17.4 x 10^-6m

1.74 x 10^-10m

The idea of quantization of energy was proposed by:

Choose an answer

Einstein

Max.Planck

Maxwell

Bohr

Rutherford

Electromagnetic radiation or photons interact with matter in

Choose an answer

two distinct ways

three distinct ways

four distinct ways

five distinct ways

An inertial frame is that frame in which

Choose an answer

a>0

a=0

a<0

none of these

Compton was awarded Nobel prize in physics in

Choose an answer

1921

1923

1925

1927

If you are moving at relativistic speed between two points that are a fixed distance apart, then the distance between the two points appers

Choose an answer

larger

shorter

equal

none of these

Converse of pair production is known as

Choose an answer

Compton effect

annihilation of matter

photoelectric effect

none of these

According to the electromagnetic wave theory of light, increasing the intensity of incident light should increase the

Choose an answer

number of photoelectrons

size of the photoelectrons

charge on photoelectrons

K.E of photoelectrons

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

Choose an answer

particular metal surface

frequency of incident light

both of them

none of them

Electromagnetic -radiation means:

Choose an answer

Photons

protons

Electrons

Mesons

None of these

Which of the following is not an example of intertial frame

Choose an answer

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

Photocell is a device which converts

Choose an answer

chemical energy into electrical energy

electrical energy into light energy

heat energy into electrical energy

light energy into electrical energy

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

Choose an answer

p = hfc

p = hf/c

p = f(hc,f)

p = cf/h

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

Choose an answer

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

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

Choose an answer

Wavelength

Frequency

Energy

Temperature

All of these

Newton's law of motion do not hold in

Choose an answer

an accelerated frame of reference

an unaccelerated frame of reference

both of these

none of these

The mass 'm' of a body moving at 0.8 c (whose rest mass is mo) becomes

Choose an answer

2 mo

1.67 mo

0.67 mo

2.67 mo

There is no way to detect:

Choose an answer

Absolute uniform motion

Accelerated motion

State rest

State of motion

None of these

Absolute motion cannot be detected

Choose an answer

in its own frame of references

in a different frame of references

both in its frame and different frame of references

none of these

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:

Choose an answer

Smaller

Lerger

Same

Much larger

None of these

If a material object moves with the speed of light 'C' its mass becomes

Choose an answer

Equal to its rest mass

Four times of its rest mass

Double of its rest mass

Infinite

The unit of work function is:

Choose an answer

Joule

Electron volt

That of threshold frequency

Both (A) and (B)

None of these

A non-inertial frame of reference is one, in which

Choose an answer

law of inertial is valid

all laws of physics are the same in all frames

a>0 or a<0

a=0

When a platinum wire is heated, it appears yellow at

Choose an answer

1600°C

900°C

1100°C

1300°C

There is certain frequency below which no electrons are emitted from the metal surface, this frequency is known as

Choose an answer

maximum frequency

minimum frequency

threshold frequency

all of these

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

Choose an answer

momentum

charge

energy

mass

Davision and Germer performed experiment to verify

Choose an answer

de-Brogile hypothesis

theory of relativity

Newton's law of gravitation

Mass-energy relation

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

Choose an answer

500°C

900°C

1100°C

1300°C

In photoelectric effect the energy of ejected electrons depend on

Choose an answer

The frequency

The intensity

Both frequency and intensity

None of these

The general theory of relativity treats problems involving

Choose an answer

inertial frame of references

accelerating frame of references

both of these

none of these

More Classes

Other Links

ECAT Pre General Science Physics Chapter 19 Dawn of Modern Physics Online Test MCQs With Answers

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer

Choose an answer