tides

Question 1

what causes tides

Answer 1

pull of moon and sun + earths rotation

Question 2

when are tides weakest

Answer 2

when sun and moon are working together

Question 3

describe low tides. tide cycles?

Answer 3

• Low tide: no net excess gravitational pull relative to centrifugal force
24 hr cycle every pt. passes through bulge 2x/day

Question 4

describe high tides

Answer 4

• High tides offset behind line between earth/moon
○ Friction of H2O and earths crust
Moon orbits off timing with earth’s spin

Question 5

are the moon and earth in time on orbit? how does the moon effect high/low tides

Answer 5

no
@ moon shifts 28.5N to 28.5S = different high/low
tides geographically.

Question 6

describe spring tides

Answer 6

• Sun directly in line with moon and earth - spring tide

Suns gravity pulls with or against moon

Question 7

why are real tides hard to describe

Answer 7

○ Topography of ocean floor/ mid-ocean ridges
○ Moons orbit and tilt of the earths axis
Coriolis effect

Question 8

describe the types of tide cycles

Answer 8

• Semidiurnal: 2/day (approx equal)
  
  • Diurnal: 1 high / 1 low tide
  • Mixed: 2 high and 2 low but unequal

Question 9

how do open ocean tides work

Answer 9

Open ocean tides: amphidromic points

Water height can vary ie high and low tides