Radiowaves

Question 1

What are the characteristics of a radio wave

Answer 1

• Radiowaves are part of the electromagnetic (EM) spectrum
• They are used for communication
• They have the longest wavelength and the shortes frequency out of the EM spectrum

Question 2

What are waves belonging to the EM spectrum

Answer 2

• Waves that are made up of oscillating electric and magnetic fields

Question 3

How can we generate waves from the EM spectrum and why does it work

Answer 3

• We can use electricity to generate waves from the EM spectrum as they are made up of oscillating electric and magnetic fields
• We can use an alternating current to do so as it is made up of oscillating charges

Question 4

How do we send and receive radiowaves

Answer 4

• Oscilliscope (generates wave) = allows us to see the frequency of the alternating current. The frequency of the AC determines the frequency of the wave
• Transmitter (sends the wave)
• Receiver (receives the wave) = absorbs energy and generates another AC of matching frequency
• Oscilliscope (displays AC matching frequency of the wave)

Question 5

Why can we use radiowaves to transmit information

Answer 5

• As both transmitted and received wave have the same frequency, we can send and receive information

Question 6

What is a long wave (radiowaves)

Answer 6

• Transfer information over huge distances (country to country)
• The wave difracts (bends) around the curved surface of the Earth

Question 7

What is a short wave (radiowaves)

Answer 7

• Transfer information over long distances (city to city)
• Transmitted wave is reflected back and forth from the ionosphere
• Also used for short distances such as bluetooth

Question 8

What is the ionosphere

Answer 8

• Electrically charged layer of the upper atmosphere

Question 9

What is a very short wave (radiowaves)

Answer 9

• Used in TVs and radio’s
• Information is sent directly from transmitter to receiver
• Buildings and other structures can cause interference and cause disturbance