Electrons of mass m and charge e are accelerated through a potential difference V and strike the target of ray tube. Which of the following is the maximum speed of these electrons?

The common door bell requires a voltage of about:

Laser is a beam of light, which is:

In Laser beam, all the photons:

Laser has use in:

An electron can never by found:

An excited atom can reside in a meta stable state for:

A potential difference of 42000 V is used in an X-Rays tube to acclerate electrons. Which of the following is the maximum frequency of the emitted x-rays?

The relation of paschen series is given as:

Which is not characteristic of Laser:

Which of the following is the energy required to remove an electron from the second orbit of hydrogen atom? (ionization potential of H. atom =13.6v)

The equation of Rydberg constant is given by:

Which of the following is the ratio of the energies of hydrogen atom in its first to second exceited state?

For which of the following transition infrared radiation will be obtained:

Atom is nearly:

Helium-neon laser, discharge tube contains neon:

Laser beam can be used to generate three dimensional images of objects in a process called:

Laser principle are of _____________ kinds

Which of the following is the ratio of K.E. to the P.E of the electron in any Bohr orbit of hydrogen atom?

The life time of most excited state atoms is about:

The meta stable state of Helium is nearly at:

The radius of hydrogen atom is about:

Helium-neon laser, discharge tube contains helium:

If V1 is the speed of electron in first orbit of hydrogen atom then velocity of the electron in 4th orbit will be Rydberg constant R and velocity of light C?

In X-Rays tube the accelerating potential appllied at the anode is V0. Which of the following will be the minimum wavelength of the emitted x-rays?

When electron jumps from fourth orbit to the second orbit, one gets the:

The incident photon is absorbed by an atom in the ground state (E1) thereby leaving the atom in the excited state (E2) is called:

In hydrogen atom electron jumps from the first orbit to second orbit, its radius

The radius of 10th orbit in hydrogen atom is:

Helium and neon have nearly identical:

The size of the nucleus of an atom (i.e. diameter of the nucleus) is the order of:

Hydrogen atom does not emit X-Rays because

Production of X-Rays is the reverse process of:

When electron in hydrogen atoms jumps from the second orbit to the first orbit, the wavelength of the emitted radiation is ? which of the following will be the wavelength of emitted radiation when electron jump from third to first orbit?

The dimensions of Planck's Constant is same as that of:

Which of the following is the dimensional formula of Rydberg's constant

The following gas was identified in the sun using spectoscopy:

Which of the following is the K.E of electron that is is accelerated through a potential of 100v

Production of X-Rays can be regarded as the inverse of:

In a electronic transition atom cannot emit:

Which of the following is the value of principle quantum number of an ionized atom

K? -Rays are produced due to tranistion of electrons from:

The most common type of lasers used in physics laboratries are:

Life time of excited states (meta stable) is:

If V is accelerating voltage then which of the following will be the maximum frequency of emitted X-Rays form X-Rays tube?

In discharge tube, electricity is conducted by:

Life of meta stable of most atoms is about:

In an X-Ray tube, the intensity of emitted X-Rays beam is increased by:

The maximum uncertainity in the measurement of positron of an electron inside the nucleus is of the order of:

The ratio of minimum to maximum wavelength in Balmer's series is:

Emission of photon of energy hf = E2-E1 in any arbitrary direction is:

The shortest wavelength of X-Rays emitted from X-Rays tube depends on the:

Laser can be made by creating:

Photon emitted in inner shell transition are:

When an electron in an atom goes from a lower to a higher orbit

The speed of electron in the nth orbit is given as:

In three phase voltage across any two lines is a:

Which of the following is the relation between energy (E) and momentum (P) of a photon?

In electronic transition , atom cannot emit:

The value of radius of 1st Bohr's orbit:

Meta stable state is:

The difference between soft and hard x-rays is of:

Population inversion is sustained in the neon gas relative to an energy level of:

Laser is the acronym of:

Laser emitted by laser device has:

Production of X-Rays can be regarded as the inverse of:

Which of the following series of hydrogen spectrum lies in ultra violet region

If electron in hydrogen atom jumps from third orbit to second orbit the emitted radiation has wavelength (R is Rydberg's constant):

Gases begin to conduct electricity at low pressure because:

Laser can only be produced if an atom is in its:

The meta stable state of neon is nearly at:

In Helium-neon laser, red laser light has energy:

Hydrogen atom spectrum does not lie in:

Atom can reside in metastable state for:

Accroding to uncertainity principle, for hydrogen atom of radius 5 x 10 -11 m, the speed of electron is:

In helium-Neon laser, discharge tube is filled with Neon gas:

The maximum number of electrons in the Bohr orbit can be

The excited states in which the life time of an electron is of the order of 10-3 sec are called:

Which of the following is the frequency of the series limit of Balmer series of hydrogen atom in terms of Rydberg constant R and velocity of Light C?

X-Rays are maximum absorbed by:

The radius of first Bohr orbit in hydrogen atom is:

The intensity of X-Rays from a Coolidge tube is plotted against wavelength ? as shown in the figure. The minimum wavelength found is ?c and the wavelength of the K? line is ?k As The accelerating voltage is increased:

Balmer series lies in:

With increasing quantum number the energy difference between in adjacent levels in atoms:

Helium-neon laser discharge tube contains neon:

In Helium-neon laser, laser light generated has the colour:

The value of Rydberg's Constant is:

In Helium-neon laser, generated red light laser has the wavelength:

Which of the following is the energy required (in ev)for ionizing an excited hydrogen atom?

Balmer Series lies in:

Production of X-Rays is the reverse process of:

For pair production, minimum energy of photon must be:

The life time of meta stable is:

If electron jumps from second orbit to first orbit in hydrogen atom it emots photon of:

Balmer Series lies in: