Use Of Electromagnetic Waves In Communication

Question 1

What is the frequency range for mobile phones

Answer 1

800MHz to 2.6 GHz

Question 2

What are some examples of electromagnetic waves?

Answer 2

Light
 x-rays
 gamma rays
 infrared
Radio waves 
microwaves

Question 3

What is the frequency for satellites

Answer 3

1 to 40 GHz (microwaves)

Question 4

What frequency does wi-fi and Bluetooth use?

Answer 4

2.4 GHz microwaves

Question 5

What is the range of a Wi-Fi router?

Answer 5

10 to 100metres

Question 6

What is the range for Bluetooth devices?

Answer 6

About 10 metres

Question 7

What is the frequency for infrared

Answer 7

The frequency of pulses is only around 40KHz

Question 8

What is the range of infrared?

Answer 8

Infrared devices have a range of just a few metres and need a clear line of sight to work

Question 9

What is special about the frequency of infrared

Answer 9

Infrared waves have high frequency but info is sent as pulses

Question 10

What does handshaking mean for devices

Answer 10

If devices want to send information to each other they need to pair through a process called handshaking

Question 11

Why is handshaking important?

Answer 11

This stops information getting lost and jumbled and there is a knowledge meant when messages are received

There may security features such as passwords and encryption

Question 12

What are the uses of spectroscopy?

Answer 12

Astronomy find out what stars are made from

Chemical analysis - flame tests

Monitoring concentrations e.g in environment studies such as oxygen levels