Question

Which of the following discovered the Radio?
A) Thomas Alva Edison
B) Guglielmo Marconi
C) James Watt
D) Charles Babbage

Answer 1

Radio: It is a transmitting device used for the transmission and reception of electromagnetic waves of radio frequency, especially those carrying sound messages. The radio spectrum is an electromagnetic spectrum. Radio frequencies from $30{\text{ Hertz}}$ to $300{\text{ GHz}}{\text{.}}$ Electromagnetic waves ranges (30 Hz to 300 GHz) frequency range, called radio waves, are widely used in modern technology, particularly in telecommunication.

Complete step by step solution:
The invention of wireless communication which led many scientists toward the discovery of radio with experiments. The experiments were performed by wireless telegraphy via inductive and capacitive induction and transmission through the groundwater.
James Clerk Maxwell showed in theoretical and mathematical relation in 1864 that electromagnetic waves could propagate through free space.
Around 1880, the first transmission of a signal was performed by David Edward Hughes by means of electromagnetic waves.

In 1888, scientist Heinrich Rudolf Hertz, conclusively proved that the transmitted airborne electromagnetic waves in an experiment confirming Maxwell's theory of electromagnetism.
After the discovery of these "Hertzian waves” many scientists and inventors experimented with transmitting and detecting Hertzian waves for further inventions.
Maxwell's theory shows that light and Hertzian electromagnetic waves had the same phenomenon at different wavelengths.

Nikola Tesla assumed Hertzian waves were relatively useless for his system since "light" could not transmit further than line of sight. In 1892 the physicist William Crookes studied and wrote on the possibilities of wireless telegraphy based on Hertzian waves.
From 1894 the Italian inventor Guglielmo Marconi built the first engineering complete, commercially successful wireless telegraphy system based on airborne Hertzian waves.

Hence the correct option is $\left( {\text{B}} \right)$.

Note: Guglielmo Marconi performed the use of radio in many fields such as marine communications and military. Guglielmo Marconi started a company for the development and propagation of radio communication services and equipment and enhanced the use of radio.