Question # 1

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 special theory of relatively treats the problems involving:

Choose an answer

Inertial frames of reference

Non-inertial frames

Non-accelerated frame

Botha (A) and (C)

Both (B) and (C)

Pair production is the phenomenon in which

Choose an answer

matter is converted into energy

energy is converted into matter

light is converted into electrical energy

electrical energy is converted into light

The value of the Stephen's constant for black body radiations is given by

Choose an answer

5.6 x 10⁸Wm^-2K^-4

5.67 x 10^-8Wm^-2K^-4

2.9 x 10^-3mK

2.9 x 10³mK

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

0.1 kg mass will be equivalent to the energy

Choose an answer

9 x 10¹⁵J

5 x 10⁸J

6 x 10¹⁶J

9 x 10^-16J

S.I. unit of planks constant is

Choose an answer

J-s^-1

J.s

J.s^-2

J.s²

When a platinum wire is heated, it appears yellow at

Choose an answer

1600°C

900°C

1100°C

1300°C

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

Choose an answer

momentum

charge

energy

mass

The stopping voltage for a certain metal is 100 volts, then the work function for the cathode plate is

Choose an answer

100 J

1.6 x 10^-17J

100 eV

1.6 x 10^-17eV

When monochromatic light is allowed to fall on cathode, it begins to emit electrons, these electrons are called

Choose an answer

thermoionic electrons

free electrons

photoelectrons

slow electrons

A black body is

Choose an answer

an ideal absorber

an ideal radiator

both of them

none of them

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

Choose an answer

Wavelength

Frequency

Energy

Temperature

All of these

Electromagnetic radiation or photons interact with matter in

Choose an answer

two distinct ways

three distinct ways

four distinct ways

five distinct ways

If A represents linear momentum and c, the velocity of light, then unit of pc in international system of units is:

Choose an answer

Newton

Joule

Joule-Sec

Joule-s^-1

Watt

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

More Classes

Other Links

Physics ECAT Pre Engineering Chapter 19 Dawn of Modern Physics 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