Question
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:

Answer

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

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

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

To increase the frequency from $100 Hz$ to $400 Hz$ the tension in the string has to be changed by ..... $times$
In Young's double slit experiment, if one of the slit is closed fully, then in the interference pattern
If the temperature of the sun were to be increased from $T$ to $2T$ and its radius from $R$ to $2R$ , then the ratio of the radiant energy received on the earth to what it was previously will be
A thin and uniform rod of mass $M$ and length $L$ is held vertical on a floor with large friction. The rod is released from rest so that it falls by rotating about its contact-point with the floor without slipping. Which of the following statement($s$) is/are correct, when the rod makes an angle $60^{\circ}$ with vertical ? [ $g$ is the acceleration due to gravity]

$(1)$ The radial acceleration of the rod's center of mass will be $\frac{3 g }{4}$

$(2)$ The angular acceleration of the rod will be $\frac{2 g }{ L }$

$(3)$ The angular speed of the rod will be $\sqrt{\frac{3 g}{2 L}}$

$(4)$ The normal reaction force from the floor on the rod will be $\frac{ Mg }{16}$

A photon collides with a stationary hydrogen atom in ground state inelastically. Energy of the colliding photon is $10.2 \ eV$. After a time interval of the order of micro second another photon collides with same hydrogen atom inelastically with an energy of $15 \ eV$. What will be observed by the detector
An inductor $20\,\, mH,$ a capacitor $100\, \mu F$ and a resistor $50 \,\,\Omega$ are connected in series across a source of emf, $V=10 sin 314 \,t .$ The power loss in the circuit is ......$W$
Consider a carnot's cycle operating between $T_1 = 500\,K$ and $T_2 = 300\,K$ producing $1\,kJ$ of mechanical work per cycle. Find the heat transferred to the engine by the reservoirs  .... $J$
It is found that electromagnetic signals sent inside glass sphere from $A$ towards $B$ reach point $C$. The speed of electromagnetic signals in glass cannot be:
Coating of strontium oxide on Tungsten cathode in a valve is good for thermionic emission because
A ball is dropped from a height of $20 \mathrm{~m}$ above the surface of water in a lake. The refractive index of water is $4 / 3$. A fish inside the lake, in the line of fall of the ball, is looking at the ball. At an instant, when the ball is $12.8 \mathrm{~m}$ above the water surface, the fish sees the speed of ball as |Take $g=10 \mathrm{~m} / \mathrm{s}^2 . \mid$