With reference to the observations in photo-electric effect, iden… - Vidyadip

MCQ

With reference to the observations in photo-electric effect, identify the correct statements from below:

$A.$ The square of maximum velocity of photoelectrons varies linearly with frequency of incident light.

$B.$ The value of saturation current increases on moving the source of light away from the metal surface.

$C.$ The maximum kinetic energy of photo-electrons decreases on decreasing the power of LED (light emitting diode) source of light.

$D.$ The immediate emission of photo-electrons out of metal surface can not be explained by particle nature of light/electromagnetic waves.

$E.$ Existence of threshold wavelength can not be explained by wave nature of light/electromagnetic waves.

Choose the correct answer from the options given below:

A
$A$ and $B$ only
✓
$A$ and $E$ only
C
$C$ and $E$ only
D
$D$ and $E$ only

✓

Answer

Correct option: B.

$A$ and $E$ only

b
$\frac{1}{2} mV _{\max }^{2}= hf -\phi$

Photoelectric effect can be explained by particle nature of light. Threshold $\lambda$ is max wavelength at which emission takes place.

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