9th grade Why the tides rise and fall worksheet

Why the tides rise and fall

Grade 9 Science Worksheet - Building Confidence

Circle the best answer.

1. 1.

   Orbit diagram of Sun, Earth and Moon with the ocean bulges drawn. What mainly causes Earth's ocean tides, by Ari's reading (NOAA)?

   • The Sun's heat warming the water
   • The Sun's gravity alone
   • Wind blowing water ashore
   • The Moon's gravity, with help from the Sun's
2. 2.

   Why does the Moon raise bigger tides than the far more massive Sun, by Kira's reading (NOAA)?

   • The Sun pulls on land but not water
   • The Sun is too hot to pull on water
   • The Moon is more massive than the Sun
   • The Moon is far closer, and tidal force drops fast with distance
3. 3.

   Earth with ocean bulges drawn, the Moon to one side. How many tidal bulges does the Moon raise on Earth's oceans, by Jun's reading (NOAA)?

   • Two: one facing the Moon, one opposite
   • Four
   • One, facing the Moon
   • One, on the far side
4. 4.

   What forms the bulge on the side of Earth away from the Moon, by Luz's reading (NOAA)?

   • The Sun's gravity pushes that water outward from Earth
   • There is no far-side bulge
   • The Moon pulls hardest on that side
   • Inertia beats the Moon's weaker pull there
5. 5.

   Earth turning through two ocean bulges. Most coasts get how many high tides each day, by Milo's reading (NOAA)?

   • Two
   • Four
   • Zero; there is just one low tide
   • One

6. Read this first

   Use this

   Moon-phase calendar for one month.

7. 6.

   When do spring tides happen, by Noah's reading (NOAA)?

   • At first and third quarter
   • At new and full Moon, when the Sun, Moon and Earth line up
   • In the spring season
   • In March and April, as the spring season brings warmer seas
8. 7.

   When do neap tides happen, by Pia's reading (NOAA)?

   • When the Moon is closest to Earth and pulls the hardest on the sea
   • In winter
   • At new and full Moon
   • At first and third quarter, with the Sun and Moon at right angles
9. 8.

   How many sets of spring tides come in each lunar month, by Ren's reading (NOAA)?

   • Two
   • Twelve, one a month through the year
   • Four
   • One, in the spring
10. 9.

    About how far apart are the two high tides on most coasts, by Tala's reading (NOAA)?

    • 12 hours 25 minutes
    • Exactly 12 hours
    • 6 hours 12.5 minutes
    • Exactly 24 hours
11. 10.

    Clock face with a lunar day marked. How long is a lunar day, by Zee's reading (NOAA)?

    • 12 hours
    • 29.5 days
    • 24 hours 50 minutes
    • Exactly 24 hours, the same as a solar day