NEETPhysicsDual Nature of Matter
An electromagnetic wave of frequency is incident on a photosensitive surface having a negligible work function. If the de-Broglie wavelength of the emitted photoelectrons is _d , what will be the slope of the straight-line graph plotted between ( _d) on the y-axis and ( ) on the x-axis?
Options
- A1 2
- B-1
- C-2
- D- 1 2
Correct answer
D. - 1 2
Step-by-step solution
From Einstein's photoelectric equation, the maximum kinetic energy of the emitted photoelectrons is given by: K_ max = h - Since the work function is negligible, K_ max = h . The de-Broglie wavelength of the electron is related to its kinetic energy by: _d = h 2mK_ max Substituting K_ max = h into the equation: _d = h 2mh = ( h 2m )^ 1/2 ^ -1/2 Taking the natural logarithm on both sides: ( _d) = ( ( h 2m )^ 1/2 ) - 1 2 ( ) Comparing this with the equation of a straight line y = mx + c , where y = ( _d) and x = ( )