P1h-stable Earth Flashcards
What are the two types of seismic waves?
P waves
S waves
What are P waves?
Longitudinal
Travel through solids and liquids
Travel trough all layers of earth
What are S waves?
Transverse
Travel through solids
Travel through outer core
What can the exposure to ultraviolet radiation cause?
Suntan Sunburn Skin cancer Cataracts Premature skin aging
How do sunscreen factors effect the damage caused by ultraviolet radiation?
Less damage when higher factors used
High factors allow longer exposure without burning
How does darker skin reduce cancer risk?
Absorb more ultraviolet radiation
Less ultraviolet radiation reaches underlying body tissues
Barry normally burns after 40 mins. He applies Sunscreen with SPF 8. How long can he stay in the sun before burning?
40 x 8 = 320 minutes
5 hours 20 minutes
How does the ozone layer protect the earth?
Absorbs some UV rays from the sun
Reduces the amount of UV radiation reaching the earths surface
How has the pollution from CFC’s affected the ozone layer?
Made it thinner
Gases react with ozone molecules and break them up
What does the depletion of the ozone layer lead to?
Allows more UV rays to reach earth
Danger to human health increases
How do scientists verify their measurements of ozone reduction?
Measurements repeated with new equipment
Measurements repeated by different scientists
Predictions tested based on the explanation
How did the discovery of the hole in the ozone layer over Antarctica changed the behaviour of society?
International bans and restrictions on CFC use
Eg
Hairspray
Coolant for fridges
What do earthquakes do and how are they detected?
Produce shock waves Cause damage to buildings and the earths surface Cause a tsunami Be detected by seismometers Recorded on seismographs
