If in a photoelectric experiment, the wavelength of incident radiation is reduced from \(6000~\mathring{A}\) to \(4000~\mathring{A}\), then:

1.	The stopping potential will decrease.
2.	The stopping potential will increase.
3.	The kinetic energy of emitted electrons will decrease.
4.	The value of the work function will decrease.

The photoelectric work function for a metal surface is 4.125 eV. The cut-off wavelength for this surface is

(1) 4125 Å                 

(2) 2062.5 Å

(3) 3000 Å                 

(4) 6000 Å

As the intensity of incident light increases,

Which of the following is dependent on the intensity of incident radiation in a photoelectric experiment

(1) Work function of the surface

(2) Amount of photoelectric current

(3) Stopping potential

(4) Maximum kinetic energy of photoelectrons

The maximum kinetic energy of photoelectrons emitted from a surface when photons of energy 6 eV fall on it is 4 eV. The stopping potential in volts is

(1) 2                     

(2) 4

(3) 6                     

(4) 10

Work function of a metal is 2.1 eV. Which of the waves of the following wavelengths will be able to emit photoelectrons from its surface ?
(1) 4000 Å, 7500 Å                     

(2) 5500 Å, 6000 Å

(3) 4000 Å, 6000 Å                     

(4) None of these

The cathode of a photoelectric cell is changed such that the work function changes from ${\mathrm{W}}_1$ to ${\mathrm{W}}_2$ $\left({\mathrm{W}}_2>{\mathrm{W}}_1\right)$. If the current before and after the change are ${\mathrm{I}}_1$ and ${\mathrm{I}}_2$, all other conditions remaining unchanged, then (assuming $\mathrm{h\nu }>{\mathrm{W}}_2$) :

(1) ${\mathrm{I}}_1$= ${\mathrm{I}}_2$               

(2) ${\mathrm{I}}_1$< ${\mathrm{I}}_2$

(3) ${\mathrm{I}}_1$>${\mathrm{I}}_2$               

(4) ${\mathrm{I}}_1<{\mathrm{I}}_2<2{\mathrm{I}}_1$

A beam of light of wavelength \(\lambda\) and with illumination \(L\) falls on a clean surface of sodium. If \(N\) photoelectrons are emitted each with kinetic energy \(E\), then:
1. \(N \propto L \) and \(E \propto L \)
2.  \(N \propto L \) and \(E \propto \frac{1}{\lambda}\)
3.  \(N \propto \lambda\) and \(E \propto L \)
4.  \(N \propto \frac{1}{\lambda}\) and \(E \propto \frac{1}{L}\)

Which of the following statements is correct

(1) The current in a photocell increases with increasing frequency of light

(2) The photocurrent is proportional to applied voltage

(3) The photocurrent increases with increasing intensity of light

(4) The stopping potential increases with increasing intensity of incident light

For the intensity \(I\) of a light of wavelength \(5000~\mathring{A}\) the photoelectron saturation current is \(0.40~\mu\text{A}\) and the stopping potential is \(1.36~\text{V},\) the work function of the metal is:
1. \(2.47~\text{eV}\)
2. \(1.36~\text{eV}\)
3. \(1.10~\text{eV}\)
4. \(0.43~\text{eV}\)