XI English Chapter 11 The Miracle of Radio

XI English Chapter 11 The Miracle of Radio

The Miracle of Radio

Q:1: At what speed do wireless waves move?
What other waves move at this speed?
The wireless waves move at the speed of 299792.5 Kilometres per second. The light waves also move at the same speed. 

Q:2: Why were wireless waves once called Hertzian waves?
Wireless waves were once called Hertzian waves because Heinrich Hertz, the German scientist was the first person who discovered these waves. 

Q:3: In what years were wireless signals first transmitted over the English Channel and the Atlantic Ocean?
Who was responsible for these successful experiments?
The wireless signals were first transmitted over the English Channel in 1896 and across the Atlantic Ocean in 1901. Marconi was responsible for both of these successful experiments. 

Q:4: What facts are given in the text about the first use of wireless to bring help to a ship in distress?
When the Liner Republic collided with another ship in Atlantic Ocean, wireless signals were, for the first time used to seek help. 

Q:5: Could speech be transmitted in the early days of wireless signalling? If not how were messages transmitted?
No, speech could not be transmitted in the early days of wireless signalling. The Morse code was sued instead of speech. 

Q:6: During what period did sound broadcasting became generally established?
Sound broad casting became generally established in 1920’s. 

Q:7: In what way is television an advance upon sound broad-casting?
Television is an advance upon sound broadcasting since pictures and not just sound can be sent by it. 

Q:8: Is television in colour possible?
If so, why is it not in general use?
Television in colour has been made possible. It is not in general use because it is expensive. 

Q:9: What is the function of Radar?
The function of Radar is to locate position of aircraft ship 

Q:10: What use can the astronomer make of radio?
The astronomer can now explore the vast universe by the use of radio telescope. It works by detecting radio waves sent by distant stars.