MCQ
Photo cell is a device to
  • A
    Store photons
  • Measure light intensity
  • C
    Convert photon energy into mechanical energy
  • D
    Store electrical energy for replacing storage batteries

Answer

Correct option: B.
Measure light intensity
b
(b) Number of electrons can be measured which are directly proportional to the intensity of radiation.

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

A parallel palate capacitor with square plates is filled with four dielectrics of dielectric constants $K_1, K_2, K_3, K_4$ arranged as shown in the figure. The effective dielectric constant $K$ will be
A parallel plate condenser is connected with the terminals of a battery. The distance between the plates is 6mm. If a glass plate (dielectric constant K = 9) of 4.5 mm is introduced between them, then the capacity will become
For a $CE$ transistor amplifier, the audio signal voltage across the collector resistance of $2.0\,k \Omega$ is $2.0\,V$. Suppose the current amplification factor of the transistor is $100$ , What should be the value of $R_B$ (in $k \Omega$) in series with $V_{B B}$ supply of $2.0\,V$ if the $dc$ base current has to be $10$ times the signal current?
The figure below shows a circuit and its input voltage $V_i$ as function of time $t$. Assuming the diodes to be ideal, which of the following graphs depicts the output voltage $V_o$ as function of time $t$ ?
The particles emitted by radioactive decay are deflected by magnetic field. The particles will be
According to Planck’s quantum theory any electromagnetic radiation is:
The radius of electron's second stationary orbit in Bohr's atom is R. The radius of the third orbit will be
Line spectra are due to
Consider three quantities $x = E/B,$ $y =\sqrt {1/{\mu _0}{\varepsilon _0}} $ and $z = l$ . Here, $l$ is the length of a wire, $C$ is a $CR$ capacitance and $R$ is a resistance. All other symbols have standard meanings.
Electric current is due to drift of electrons in