EM Spectrum Flashcards
1
Q
What are 4 things that the members of the EM spectrum all have in common?
A
- All transverse waves.
- Can all travel through a vacuum.
- All transfer energy.
- Can all be reflected, refracted and diffracted.
2
Q
What are 3 types of waves that can be used for communicating?
A
- Light
- Microwaves
- Radio waves
3
Q
What are two types of waves used for cooking?
A
- microwaves
- Infra Red
4
Q
What type of wave can be used to treat cancer?
A
Gamma
5
Q
What type of wave can be used to see people in the dark?
A
Infra red
6
Q
A type of wave used for radar
A
Microwaves
7
Q
Why do microwave ovens cook food faster than normal ovens?
A
- Water molecules within food absorb microwaves & become hot.
- Food cooked throughout, not just from outside like normal oven.
8
Q
How can x-rays be used to check for broken bones?
A
- X-rays are absorbed by bone and can pass through soft tissue.
- photographic film turns black in areas exposed to x-rays.
- film remains white in areas not exposed to x-rays.
9
Q
Why is it important not to damage the ozone layer around the earth?
A
- The ozone layer absorbs large amounts of the Sun’s UV radiation.
- If layer is damaged, more UV light will reach Earth’s surface.
- UV light is harmful to human eyes and can cause skin cancer.
10
Q
Why does food stay fresher for longer after being exposed to gamma radiation?
A
Gamma kills microorganisms in food, so delays decay.
11
Q
What dangers do these types of radiation have and what precautions can be taken?
- X-Ray
- Microwaves
- Infra Red
- UV
A
- X-Ray: cancer: lead screening
- microwaves: cancer: metal screening
- infra red: skin burns: avoid over exposure
- UV: cancer: glasses, sun cream
