OZ 2- Screening The Sun

Question 1

What has shorter wavelength- radio waves or gamma rays?

Answer 1

Gamma

Question 2

Which has higher frequency- radio waves or x rays?

Answer 2

X-rays

Question 3

Which colour in visible light spectrum has greater energy- red or violet?

Answer 3

Violet

Question 4

How do you calculate wavelength of wave?

Answer 4

Speed of light divided by frequency

Question 5

In particle theory, light is described as…

Answer 5

Stream of photons (packages of energy)

Question 6

What is Planck constant?

Answer 6

6.63 x 10^-34

Question 7

How is the energy of 1 photon calculated?

Answer 7

Planck constant times frequency

Question 8

Which type of UV ray has shortest wavelength and therefore does not penetrate the ozone layer?

Answer 8

UV-C

Question 9

How does UV-A radiation cause cancer?

Answer 9

Penetrates skin, releasing free radicals which can change structure of DNA and cause cancer

Question 10

What occurs when radiation interacts with matter?

Answer 10

Energy is transferred to molecules involved, and changes occur depending on amount of energy

Question 11

What are the 4 types of behaviours associated with molecules when interacting with radiation

Answer 11

1. Translational energy
2. Rotational energy
3. Vibrational energy
4. Electronic energy

Question 12

What kind of behaviour of molecules does visible and UV light cause?

Answer 12

Electronic energy, causes-

• electrons to leave to higher energy level and release energy
• photodissociation (breaking of bonds)
• ionisation

Question 13

What behaviour of molecules does infrared light cause?

Answer 13

Vibrational energy

Question 14

Why can we feel infrared energy?

Answer 14

• causes molecules in skin to vibrate more, feel it as heat