TH 8 GRADE Science Pull of Gravity on

TH 8 GRADE Science

Pull of Gravity on the Earth 8. E. 4 B. 2 Construct explanations for how gravity affects the motion of objects in the solar system and tides on Earth. –page 7 in the ISN(students need to draw a picture the represented the indicator. (Title page and picture –page 7)

KWL Chart-page 8 What I Know What I want to Know What I Learned

Tides and planetary orbits are caused by the pull of gravity Pages 9 -10(Notes) • Effects of Mass and Distance on Gravitational Force • The more massive an object, the greater it’s gravitational pull. • The closer the distance between objects, the greater the gravitational pull • The gravitational pull between the Sun and the planets and between Earth and its Moon cause distinct motions between and among these bodies

Effects of Gravity on Planetary Orbits Pages 9 -10(Notes) • The Sun’s gravitational attraction, along with the planet’s inertia (continual forward motion), keeps the • planets moving in elliptical orbits (Earth’s orbit is slightly oval) and determines how fast planets nearer the Sun move/orbit faster than planets farther from the Sun because the gravitational attraction is greater. • When a planet is farther from the Sun, the gravitational attraction between them decreases and the planet moves/orbits slower orbit.

Effects of Gravity on Tides Pages 9 -10(Notes) • Since the Moon is closer to Earth than the Sun (distance), the Moon has the greatest pulling effect on • tides, the rise and fall of Earth’s waters. • The Sun also pulls on Earth and can combine its force with the Moon causing even higher tides, spring tides or can be a right angles, pulling against the Moon’s pull, causing very little tidal change, neap tides.

Vocabulary Mapping-page 11 in the ISN • Neap Tide • Spring Tide (See example on the Wall)