Einstein's Photoelectric Equation - Practice Questions & MCQ

When photons of wavelength λ₁ are incident on an isolated sphere, the corresponding stopping potential is found to be V.  When photons of wavelength  λ₂ are used, the corresponding stopping potential is thrice that of the above value. If light of wavelength  λ₃ is used then find the stopping potential for this case :

Question contains Statement-1 and Statement-2. Of the four choices given after the statements, choose the one that best describes the two statements.

Statement-1: When ultraviolet light is incident on a photocell, its stopping potential is and the maximum kinetic energy of the photoelectrons is . When the ultraviolet light is replaced by X-rays, both and increase.

Statement-2:  Photoelectrons are emitted with speeds ranging from zero to a maximum value because of the range of frequencies present in the incident light.

This question has Statement-1 and Statement-2. Of the four choices given after the statements, choose the one that best describes the two statements :

Statement 1: A metallic surface is irradiated by a monochromatic light of frequency  (the threshold frequency). The maximum kinetic energy and the stopping potential are and  respectively. If the frequency incident on the surface is doubled, both the  and   are also doubled.

Statement 2: The maximum kinetic energy and the stopping potential of photoelectrons emitted from a surface are linearly dependent on the frequency of incident light.

Two identical photo cathodes receive light of frequencies . If the velocities of the photoelectrons (of mass m ) coming out are respectively , then

According to Einstein’s photoelectric equation, the plot of the kinetic energy of the emitted photoelectrons from a metal and the frequency of the incident radiation gives a straight line whose slope is:

The potential difference that must be applied to stop the fastest photoelectrons emitted by a nickel surface, having work function 5.01 eV, when ultraviolet light of 200 nm falls on it, must be:

For photoelectric emission from certain metal the cut-off frequency is v. If radiation of frequency 2v impinges on the metal plate, the maximum possible velocity of the emitted electron will be (m is the electron mass)

Light of two different frequencies whose photons have energies 1 eV and 2.5eV respectively illuminate a metallic surface whose work function is 0.5 eV successively. Ratio of maximum speeds of emitted electrons will be

For photoelectric emission from certain metal the cutoff frequency is . If radiation of frequency 2 impinges on the metal plate, the maximum possible velocity of the emitted electron will be (m is the electron mass):