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 capacitor of capacity $C_1$ is charged to the potential of $V_0$. On disconnecting with the battery, it is connected with a capacitor of capacity $C_2$ as shown in the adjoining figure. The ratio of energies before and after the connection of switch S will be
A voltmeter having a resistance of 998 ohms is connected to a cell of e.m.f. 2 volt and internal resistance 2 ohm. The error in the measurement of e.m.f. will be
There are two sources kept at distances $2 \lambda$. A large screen is perpendicular to line joining the sources. Number of maximas on the screen in this case is $(\lambda=$ wavelength of light $)$
Which of the following of a radioactive material is a measure of its instability?
A battery has $e.m.f.$ $4\, V$ and internal resistance $r$. When this battery is connected to an external resistance of $2\, ohms$, a current of $1\, amp$. flows in the circuit. How much current will flow if the terminals of the battery are connected directly .......... $amp$
When $\sqrt 3 $ $ampere$ current is passed in a tangent galvanometer, there is a deflection of $ 30° $ in it. The deflection obtained when $3$ $ampere$ current is passed, is.....$^o$
A convex lens is dipped in a liquid whose refractive index is equal to the refractive index of the lens. Then its focal length will:
The graph which represents the correct variation of logarithm of activity $(log\, A)$ versus time, in figure is
Two infinitely long wires each carrying current $I$ along the same direction are made into the geometry as shown in the figure below. The magnetic field at the point $P$ is
Point charge ${q_1} = 2\,\mu C$ and ${q_2} = - 1\,\mu C$ are kept at points $x = 0$ and $x = 6$ respectively. Electrical potential will be zero at points