The photoelectric threshold wavelength of a certain metal is $3000 \mathring{A}$. If the radiation of $2000 \mathring{A}$ is incident on the metal,then:

Consider the two following statements $A$ and $B$, and identify the correct choice given in the answers :
$(A)$ In photovoltaic cells, the photoelectric current produced is not proportional to the intensity of incident light.
$(B)$ In gas-filled photoemissive cells, the velocity of photoelectrons depends on the wavelength of the incident radiation.

The threshold wavelength for the emission of photoelectrons from a material is $5200\, \text{\AA}$. Which of the following monochromatic light sources will cause the emission of photoelectrons from this surface?

In the photoelectric effect,the photocurrent:

Give an outline of the experimental study of the photoelectric effect.

The anode voltage of a photocell is kept fixed. The frequency of the light falling on the cathode is gradually increased. Then the correct graph which shows the variation of photo current $I$ with the frequency $\nu$ of incident light is