Upper layers, escape velocity and ozone
Answers are for parents and teachers.
1
Change the escape velocity 11.2 km/s into km/h.
11.2 × 3600 = 40 320 km/h.
2
A planet has Ve = 5 km/s. Gas X has Vrms = 0.4 km/s and gas Y has 6 km/s. Which does the planet keep, by the book’s rule?
Gas X (0.4 < 5). Gas Y drifts away (6 > 5).
3
Write the two steps of ozone formation.
O₂ + UV → O + O, then O + O₂ → O₃.
4
Give three harms to people when more UV reaches the ground.
Skin DNA damage (possible skin cancer), weaker immune cells, eye lens damage (cataract).
5
Why does Mercury cool so fast at night?
It has no atmosphere to hold the heat.