Lecture 22 (end of exam 2 material)

Question 1

What was the main question 100-150 years ago?

Answer 1

What is light and colour

Question 2

What spectrum is visible light apart of

Answer 2

Electromagnetic

Question 3

Light is a _____

Answer 3

wave

Question 4

All light ____ have the ____ speed

Answer 4

Wave the same

Question 5

What is the differences in different light?

Answer 5

The distance from peak to peak called wavelength

Question 6

Wave length and energy are _____ related

Answer 6

inversely

Question 7

____ the wave length the _____ the energy

Answer 7

Larger , lower

Question 8

What are the most powerful type of light?

Answer 8

Gamma rays

Question 9

The human eye can see wavelengths from ____ nm to _____ nm

Answer 9

380 to 740

Question 10

What colour is 380 nanometers?

Answer 10

purple

Question 11

What colour is 740 nanometers?

Answer 11

Red

Question 12

Radio waves have the ____ wave lengths

Answer 12

longest

Question 13

What are the three things that can happen when light hits matter?

Answer 13

1) Can reflect off
2) Pass through
3) Be absorbed

Question 14

True or false; Different wavelengths of light react the same to different things

Answer 14

False; react differently

Question 15

Why do plants look green?

Answer 15

Because plants absorb red and blue light to make glucose and reflect green light

Question 16

What is just past visible light that has longer wavelengths and less energy?

Answer 16

Infrared light

Question 17

what is infrared light?

Answer 17

heat

Question 18

What is just past visible light that has shorter wavelengths and more energy?

Answer 18

Ultra violet light (UV light)

Question 19

What things is infrared light associated with in the atmosphere?

Answer 19

1) Greenhouse effect
2) Global warming
3) Climate change

Question 20

What things is UV light associated with in the atmosphere?

Answer 20

1) Production of the ozone

2) Hole in the ozone

Question 21

What visible color has the lowest energy

Answer 21

red light

Question 22

Why was there no life on land until 400 million years ago?

Answer 22

Because the UV light would damage and break the DNA of any organism

Question 23

What are the three types of UV light and what are there wavelengths?

Answer 23

a) UVA : 320-400 nm
b) UVB : 280-320 nm
c) UVC : <280 cm

Question 24

Which type of UV light is most damaging to tissue and DNA?

Answer 24

UVC

Question 25

UVC plus oxygen results in what? and where does this occur

Answer 25

2O

in the stratosphere (30-50km above earth surface)

Question 26

O plus Oxygen results in what?

Answer 26

O3 (The ozone)

Question 27

O3 (ozone) plus UVB results in what?

Answer 27

O and oxygen

Question 28

What type of UV light reaches the earth surface and what does it cause?

Answer 28

UVA causes sun tans

Question 29

Ozone is only seen above the ____

Answer 29

Troposphere

Question 30

What units do we use to measure the ozone?

Answer 30

Dobson units (DU)

Question 31

If one removes all the gases but the ozone and then compresses the ozone to 1ATM how thick would the atmosphere be?

Answer 31

3 mm or 300 DU

Question 32

When was the hole in the ozone first mentioned, in what article and by who

Answer 32

Nature, May of 1985 and by Farman

Question 33

What did Farman state in his article?

Answer 33

That in September 1984 “suddenly and unexpectedly” The ozone had dropped by 50% and returned 6 weeks later