Question

According to Einstein's photoelectric equation, the plot of the kinetic energy of the emitted photoelectrons from a metal $V_{s}$ the frequency, of the incident radiation gives a straight line whose slope

• A. Depends on the nature of the metal used
• B. Depends on the intensity of the radiation
• C. Depends both on the intensity of the radiation and the metal used
• D. Is the same for all metals and independent of the intensity of the radiation

Answer 1

Answer: (D)

Einstein's photoelectric equation is
$K E_{m a x}=hv-\phi$ ...(i)


The equation of line is
$y=mx+c$ ...(ii)
Comparing above two equations
$m=h, \, c=-\phi$
Hence, slope of graph is equal to Planck's constant (non-variable) and does not depend on intensity of radiation.