Question
Write Einstein’s photoelectric equation. State clearly the three salient features observed in photoelectric effect, which can be explained on the basis of the above equation.
✓
Answer
Einstein’s photoelectric equation:
$\text{K}_{max} = \text{hv} - \phi_{0} = \text{h}(\text{v} - \text{v}_{0})$
$\text{K}_{max} = \text{hv} - \phi_{0} = \text{h}(\text{v} - \text{v}_{0})$
- $\text{K}_{max} $ of electrons depends linearly on v.
- $\text{K}_{max}$ is independent of intensity of radiation.
- There exists a threshold frequency $\text{v}_{0}\it{( = \phi_{0}/\text{h})}$ for the metal surface, below which no photoelectric emission is possible. (No matter how intense the incident radiation may be or how long it falls on the surface.)
- For $v > v_0$, photoelectric current is proportional to intensity of incident radiations.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
What should be the value of R in the figure. for which the current in it is zero?
Use de- Broglie’s hypothesis to write the relation for the nth radius of Bohr orbit in terms of Bohr’s quantization condition of orbital angular momentum.
Answer the following question:
In a single slit diffraction experiment, the width of the slit is made double the original width. How does this affect the size and intensity of the central diffraction band?
In a single slit diffraction experiment, the width of the slit is made double the original width. How does this affect the size and intensity of the central diffraction band?
Draw a graph from the following data. Draw tangents at x = 2, 4, 6 and 8. Find the slopes of these tangents. Verify that the curve drawn is $y = 2x^2$ and the slope of dy tangent is $\tan\theta=\frac{\text{dy}}{\text{dx}}=4\text{x}.$
→| x | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
| y | 2 | 8 | 18 | 32 | 50 | 72 | 98 | 128 | 162 | 200 |
A pivoted aluminium bar falls much more slowly through a small region containing a magnetic field than a similar bar of an insulating material. Explain.
A platinum resistance thermometer reads $0^\circ$ when its resistance is $80\Omega$ and $100^\circ$ when its resistance is $90\Omega$. Find the temperature at the platinum scale at which the resistance is $86\Omega$.
→A block of mass $m$ is attached to two unstretched springs of spring constants $k_1$ and $k_2$ as shown in figure. The block is displaced towards right through a distance $x$ and is released. Find the speed of the block as it passes through the mean position shown.
→The minimum deviations suffered by red, yellow and violet beams passing through an equilateral transparent prism are 38.4°, 38.7° and 39.2° respectively. Calculate the dispersive power of the medium.
Find the maximum wavelength of electromagnetic radiation which can create a hole-electron pair in germanium. The band gap in germanium is 0.65eV.
Describe the two experiments related to static friction with diagram.