Unit One: Light Forces Flashcards
What are the functions of Light on Earth
there are two (2) of them
- Source of Energy for all organisms
- Source of information (navigation, time)
What is Light
- electromagnetic radiation from the sun
- source of energy for nuclear reactions
- energy travels through electromagnetic waves
What causes the delay in vision from sunlight to human eye?
a delay in neurotransmitters
How long does it take for sunlight to reach organisms from the sun
Approx 8 minutes
What is the distance from the sun to the earth
147-152 (10^6) km
What is the common travelling speed of light
1.1 (10^9) km/h
What are the two aspects to electromagnetic waves
1. Wavelength
2. Frequency
If an electromagnetic wave is short, what can be said about it’s occelation?
Shorter Waves = QUICK occelation
Occelation: repeated motion in state (quick occelation = quicker wave)
What are the two components of electromagnetic waves
Think composition
1. Oscillating Electrical Component
2. Comoving Magnetic Component
What does the electromagnetic spectrum look like?
(from shortest high energy to longest low energy)
1. Gamma Rays
2. X-Rays
3. Ultraviolet Radiation
4. Near-Infrared Radiation
5. Infrared Radiation
6. Microwaves
7. Radio Waves
What are the 3 potential situations that could occur when light hits an object?
1. Reflection
2. Refracted
3. Asborbed
What is Reflection
bullet points
- electromagnetic waves “bounce” off object
- gives rise to visible colours
- can be reflected and bounced onto something else
What is Refraction
bullet points
- light moves through an object
- rays can change angle and alter an image
- cleaning net in a swimming pool
What is Absorption
bullet points
- biological organisms absorb light
- skin cells absorb light
- light energy will excite atoms
