Introducing 

Prezi AI.

Your new presentation assistant.

Refine, enhance, and tailor your content, source relevant images, and edit visuals quicker than ever before.

Loading content…
Transcript

Radio waves

Radio waves have wavelengths ranging up to the length of 1000 American football fields lined up one after the other.

Describe the role of electromagnetic waves in: 

– radio and television communications (radio waves) RUH

– satellite television and telephones (microwaves) _EAMON

– electrical appliances, remote controllers for televisions and intruder alarms (infrared) SAM

– medicine and security (X­rays) EMILE

  Demonstrate an awareness of safety issues regarding the use of microwaves and X­rays

In 1873, James Clerk Maxwell published a book in which he speculated the idea that electricity and magnetism were combined into one force rather than two, which had been the previous belief.

And there you have it.

Electricity and magnetism: electromagnetism.

Humans wanted to this force for themselves and eventually found ways of harnessing some of the many powers of the electromagnetic spectrum.

Here are some (fairly simple) explanations of these "powers".

The Secret Life of

Waves:

The Electromagnetic Spectrum

Eamon, Sam, Emile and Ruhamah

Using Infrared Waves-Sam

Infrared radiation is used in

electrical heating.

Television

Radio

The sound is transformed into waves to travel.

These waves all have different frequencies.

A radio has an antenna.

The antenna will pick up these different waves (radio signals).

A tuner can be tuned to a certain frequency so that the radio antenna only picks up the waves with that specific frequency.

The waves are transformed back into sound.

Then you hear the sound.

In telecommunication, we now sometimes use telecommunication satellites.

Waves are sent to satellites (by antennas), again at different frequencies to distinguish them.

The satellites then either send them back to earth with reflectors to have a single, precise beam.

This means that if the antennas on the ground aren't properly lined in place, the entire signal could be lost

Another type of transmission is called in-band. This allows for the digital signals to be carried by normal AM or FM radio waves.

We say that the information "piggy-backs" on the other transmission.

Infrared sensors & Alarms

These sensors work by detecting

a rapid change in infrared wavelength.

Thermography

The human body emits a 9-10 micro millimeter wavelength from our body heat.

So when person moves, the sensor detects the movement of waves and goes off.

Thank You!

The Binary Codes

Bibliography

Medical uses of X-Rays

X-Rays in Security

http://www.darvill.clara.net/emag/emagmicro.htm

http://imagine.gsfc.nasa.gov/docs/science/know_l1 emspectrum.html

http://i00.i.aliimg.com/photo/v0/140793352/Far_Infrared_Heating_Panel.jpg

http://en.wikipedia.org/wiki/Infrared#Communications

http://electronics.howstuffworks.com/remote-control2.htm

http://home.howstuffworks.com/home-improvement/household-safety/security/question238.htm

http://en.wikipedia.org/wiki/Radio_wave#Radio_communication

http://science.hq.nasa.gov/kids/imagers/ems/radio.html

http://www.cnes.fr/web/CNES-en/1109-how-telecommunications-satellites-work.php

http://en.wikipedia.org/wiki/X-ray#Medical_uses

http://science.howstuffworks.com/transport/flight/modern/airport-security4.htm

http://en.wikipedia.org/wiki/X-ray_generator

Button 1 = 000 0000

Button 2 = 000 0001

Button 3 = 000 0010

Button 4 = 000 0011

Channel Up = 001 0001

Channel Down = 001 0001

Power On = 001 0101

Power Off = 010 1111

Volume Up = 001 0010

Volume Down = 001 0011

X- Rays are used in airport security to detect items in luggage and classify things in three categories:

  • Metal
  • inorganic
  • organic

In the medical field X-rays are used in a similar way as in security but to detect things like bone fractures. Bones contain lots of calcium which absorbs X-rays very well and thus less rays reach the detector so that we can create a very clear image of the bones.

TV Remotes

The rays are emitted, pass through the object and then are read by a detector

X-Rays can also detect things like lung cancer, pneumonia, and kidney stones

When the button is pressed, the circuit sends the binary command with infrared waves to the TV

X-Rays are less useful for imaging of very sift tissue such as brain or muscle tissue

X-Rays contain a lot of energy and therefore they can pass through a lot of things. Different things absorb different amounts of the rays and when the rays reach the energy detector the amount of energy that reaches the detector is used to create an image of items in a bag.

X-ray of an arm, showing very clear damage to the bones

X-Ray of a bag

When the Waves reach the TV,

There is a sensor which converts the infrared waves into electrical signals.

Microwaves

The prefix-The wavelength of microwaves range from 1mm to 1m.

Learn more about creating dynamic, engaging presentations with Prezi