Electromagnetic Spectrum Flashcards
What is an electromagnetic wave?
A transverse wave caused by oscillations in an electromagnetic field.
All electromagnetic waves:
Transfer energy as _____________ from the source of the waves to an absorber.
Can ________________________ such as in space.
Travel at the __________________________ through a vacuum or the air.
radiation
travel through a vacuum
same speed of 3.0 x 10 8
What is the order of the electromagnetic spectrum from lowest frequency to highest frequency:
(Red Monsters Imitate Vampires Under Xylophones Graciously)
1.
2.
3.
4.
5.
6.
7.
- Radio waves
- Microwaves
- Infrared radiation
- Visible light
- Ultraviolet radiation
- X-rays,
- Gamma rays
In the electromagnetic spectrum, the lower the frequency, the ___________________ and the ________________.
The higher the frequency, the __________________ and ___________________.
longer the wave
lower the energy
shorter the wave
higher the energy
Why are radio waves suitable for communication?
Radio waves are ___________________ through air. They do not cause ____________________ by the human body, and they can be _____________ to _____________________.
transmitted easily
damage if absorbed
reflected
change their direction
Radio waves can be produced by oscillations in electrical circuits.
When radio waves are _______________________, they create an ____________________.
This electrical current has the ___________________________________.
________________________________ before transmission, which can then be _____________ when the wave is received to broadcast information.
absorbed by a conductor
alternating current
same frequency as the radio waves
Information is coded into the wave
decoded
Microwaves have frequencies which are easily absorbed by molecules in food.
What happens to the internal energy of the molecules and what does it cause?
The internal energy of the molecules increases when they absorb microwaves, which causes heating.
Infrared light has frequencies which are absorbed by some chemical bonds.
The internal energy of the bonds increases when they absorb infrared light, which causes heating.
What 2 things is infrared light used for?
Electric heaters and thermal imaging.
Ultraviolet waves, X-rays and gamma rays can ___________________________, producing electrically charged ______.
add or remove electrons
ions
What are 2 health effects of electromagnetic waves:
Ultraviolet waves can increase the risk of ______________.
X-rays and gamma rays can cause the _________________, which can lead to _________.
skin cancer
mutation of genes
cancer
Explain why X-rays can be used to produce images of the bones inside the body. (2)
X-rays are absorbed by bone.
But can pass through flesh.
Explain how electrical signals in a transmitter produce a signal in a receiver. (3)
The ________________ in the transmitter also produces ________________.
Radio waves are __________ by the receiver when __________ the ________________ at the same ___________.
electrical current
radio waves
absorbed
inducing
electrical current
frequency