Dual Nature of ...

A particular hydrogen like atom has its ground state binding "energy 122.4 eV. Its is in ground state. Then :

The electron in a hydrogen atom makes a transition n₁  ¾→ n₂ , where n₁  &n₂  are the principal quantum numbers of the two states. Assume the Bohr model to be valid. The time period of the electron in the initial state is eight times that in the final state. The possible values of n₁  &n₂  are :

 A beam of ultraviolet light of all wavelengths passes through hydrogen gas at room temperature, in the x-direction. Assume that all photons emitted due to electron transition inside the gas emerge in the y-direction. Let A and B denote the lights emerging from the gas in the x and y directions respectively.

If radiation of allow wavelengths from ultraviolet to infrared is passed through hydrogen agas at room temperature, absorption lines will be observed in the :

In the hydrogen atom, if the reference level of potential energy is assumed to be zero at the ground state level. Choose the incorrect statement.

Statement-1: Figure shows graph of stopping potential and frequency of incident light in photoelectric effect. For values of frequency less than threshold frequecy (v₀ ) stopping potential is negative.

Statement-2 : Lower the value of frequency of incident light (for n >n₀ ) the lower is the maxima of kinetic energy of emitted photoelectrons.

Statement-1: In the process of photo electric emission, all the emitted photoelectrons have same K.E.

Statement-2: According to einstein 's photo electric equation KE_max  = hn – f.

Statement-1: Work function of aluminum is 4.2 eV. If two photons each of energy 2.5 eV strikes on a piece of aluminum, the photo electric emission does not occur.

Statement-2: In photo electric effect a single photon interacts with a single electron and electron is emitted only if energy of each incident photon is greater then the work function.

Statement-1: An electron and a proton are accelerated through the same potential difference. The deBroglie wavelength associated with the electron is longer.

Statement-2: De-Broglie wavelength associated with a moving particle is l =  where, p is the linear momentum and both have same K.E.

Statement-1: Two photons having equal wavelengths have equal linear momenta.

Statement-2: When light shows its photon character, each photon has a linear momentum p = .

 A parallel beam of uniform, monochromatic light of wavelength 2640 A has an intensity of 200 W/m² . The number of photons in 1 mm³  of this radiation are ...............

The total energy of the electron in the hydrogen atom in the ground state is -13.6 eV. Which of the following is its kinetic energy in the first excited state?

When a monochromatic point source of light is at a distance of 0.2 m from a photoelectric cell, the cut off voltage and the saturation current are respectively 0.6 volt and 18.0 mA. If the same source is placed 0.6 m away from the photoelectric cell, then find

Q

the stopping potential  

When a monochromatic point source of light is at a distance of 0.2 m from a photoelectric cell, the cut off voltage and the saturation current are respectively 0.6 volt and 18.0 mA. If the same source is placed 0.6 m away from the photoelectric cell, then find

Q. 

the saturation current

An isolated metal body is illuminated with monochromatic light and is observed to become charged to a steady positive potential 1.0 V with respect to the surrounding. The work function of the metal is 3.0 eV. The frequency of the incident light is ___________________ eV.

663 mW of light from a 540 nm source is incident on the surface of a metal. If only 1 of each 5 ×10⁹  incident photons in absorbed and causes an electron to be ejected from the surface, the total photocurrent in the circuit is ____________________.