1. Tides
Video

2. High tides are higher than usual Low tides are higher than usual.
SPRING TIDES
Occur when :
High tides are higher than usual
Low tides are higher than usual.
They occur twice a day
Occur at a New Moon and Full Moon (At a horizontal line)

4. Spring tide (Horizontal line)

5. Spring tide (Sun on the right)

6. Spring tide

7. High tides are lower than usual Low tides are higher than usual
NEAP TIDES
Occur when:
High tides are lower than usual
Low tides are higher than usual
They occur twice a day
They occur at a 1st Quarter and Third Quarter (at 90 degree angles)

12. They alternate every 6 hours
Most know for exam
In one day we have:
Two high tides and
Two low tides
They alternate every 6 hours

14. Low tides and High tides

15. Effect on the tides
Spring tides: Strong effect on tides (New and Full)
Neap Tides: Medium effect on tides (1st and 3rd quarter)
Low effect:
Wax Crescent
Wax Gibbous
Wan Crescent
Wan Gibbous

16. Interactive