MCQ
An antenna is a device
  • A
    That converts electromagnetic energy into radio frequency signal
  • B
    That converts radio frequency signal into electromagnetic energy
  • That converts guided electromagnetic waves into free space electromagnetic waves and vice-versa
  • D
    None of these

Answer

Correct option: C.
That converts guided electromagnetic waves into free space electromagnetic waves and vice-versa
c
(c) An antenna is a metallic structure used to radiate or receive $EM$ waves.

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 group of $N$ cells whose $emf$ varies directly with the internal resistance as per the equation $E_N = 1.5\, r_N$ are connected as shown in the figure below. The current $I$ in the circuit is ........... $amp$
If $\mu_c$ and $\mu_h$ are electron and hole mobility, $E$ be the applied electric field, the current density $j$ for intrinsic semiconductor is equal to
Dimensions of $\frac{1}{(\mu_0\in_0)}$ is:
The focal lengths of convex lens for red and blue light are 100 cm and 96.8 cm respectively. The dispersive power of material of lens is
An electron is accelerated through a potential difference of 200 volts. If e/m for the electron be $1.6\times 10^{11}$  coulomb/kg, the velocity acquired by the electron will be
A singly ionized magnesium atom $(A=24)$ ion is accelerated to kinetic energy $5\,keV$ and is projected perpendicularly into a magnetic field $B$ of the magnitude $0.5\,T$. The radius of path formed will be___________ $cm$
The value of plate current in the given circuit diagram will be...$mA$
An e.m.f. of 12 volts is induced in a given coil when the current in it changes at the rate of 48 amperes per minute. The self inductance of the coil is
A semiconductor device is connected in a series circuit with a battery and a resistance. A current is found to pass through the circuit. If the polarity of the battery is reversed, the current drops almost to zero. The device may be
If the amplitude ratio of two sources producing interference is $3 : 5$, the ratio of intensities at maxima and minima is