In ruby laser, the stimulated emission is due to transition from

A direct current I flows along the length of an infinitely long straight thin walled pipe, then the magnetic field is

convex lens made of glass has focal length 0.15m in air. If the refractive index of glass is 3/2, and that of water is 4/3 the focal length of lens when immersed in water is

Two sources are said to be coherent if they produce waves

Three resistors 1 Ω, 2 Ω, 3Ω resistor a 3 V battery is connected. The current through 3 Ω resistor is -

In a common emitter amplifier the input signal is applied across

Adding detergents to water helps in removing dirty greasy stains. This is because
1. It increases greasy stains. This is because
2. It decreases the oil-water surface tension
3. It increases the viscosity of the solution
4. Dirt is held suspended surrounded by detergent molecules

Choose the correct statement (a) for a cricket ball that is spinning clockwise through air
S1 : Statemlines of air are symmetric around the ball.
S2 : The velocity of air above the ball relative to it is larger than that below the ball.
S3 : The velocity of air above the ball relative to it is smaller than that below the ball.
S4 : There is a net upward force on the ball.

Ferromagnetic materials used in a transformer must have

According to Newton’s corpuscular theory, the speed of light is

For the constructive interference the path difference between the two interfering waves must be equal to

The accurate measurement of emf can be obtained using

A person, with outstretched arms, is spinning on a rotating stool. He suddenly brings his arms down to his sides. Which the following is true about his kinetic energy K and angular momentum L?

Which of the following is not a thermodynamic coordinate?

An antenna uses electromagnetic waves of frequency 5 MHz . For proper working, the size of the antenna should be

Temperature can be expressed as derived quantity in terms of

Electron volt is a unit of

Dimensions of impulse are

Potential is measured in

One Nanometer is equal to

Maxwell is the unit of

Which of the following is derived physical quantity ?

What are the units of magnetic permeability ?

The dimensions of pressure gradient are

The dimensions of Rydberg's constant are

'Farad' is the unit of

S.I. unit of surface tension is

Which one of the following pairs does not have the same dimension ?

Which one of the following physical quantity has the same unit as that of pressure ?

The symbol of SI unit of inductance is H. It stands for

Light year is a measure of

Which one of the following is not a dimension less quantity ?

The dimensions of universal gas constant are

The dimensions of magnetic moment are

The dimensions of Wien's constant are

Plant viruses usually contain :

Viruses were discovered by :

Which statement best defines viruses?

Which infectious agents consist essentially of small, naked RNA molecules without a protein coat?

Coliphage f X 174 contains :

Viruses differ from living organisms in that, they :

Virus which attacks E.coli is called :

Which characteristic distinguishes viruses from cellular organisms?

The genome of a temperate bacteriophage integrated into the bacterial chromosome is termed as?

Virus was crystallized and isolated first by :

Little leaf disease of brinjal is primarily associated with which pathogen?

Which approximate size range includes many of the smallest known conventional virus particles?

Which of the following is devoid of protein coat, with a constitution of RNA only ?

Genetic modification brought about by a virus in a bacteria is known as :

Which property makes the classification of viruses as strictly living or non-living problematic?