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OBJECTIVES: By the end of today’s lesson, you will be able to…

SWBAT explain how the gravity of the moon causes tides in Earth’s oceans.

DO NOW Directions: Using the pictures to help, define the following terms.

Term/Picture Definition Solar Eclipse

Lunar Eclipse

Umbra

7th Grade

Science

Unit: Earth, Sun, and Moon Lesson: ESM 9_ Tides 1

Name: __________________________________ Date: Thursday, October 27, 2016 Homeroom: ___________________________

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Practice Beyond Perfection!!

Draw all 8 planets in our solar system, given the position of the sun below. Be sure to make each planet look

different, and put them in the correct order!

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I DO – CLASS NOTES

Specialized Terminology

Tides- Tides are the ___________ and ___________ of sea levels caused by

the gravitational forces exerted by the Moon and the Sun.

Examples:

High tide (the level of the ocean at its highest point)

Low tide (the level of the ocean at its lowest point).

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Why do you think a moon can’t have a larger mass than its planets?

Gravity- the force of ___________________ between

all masses in the universe. The ________________ the

mass of an object, the more gravitational pull it will have.

This is why all of the planets orbit the _________.

Gravity is a major ______________ responsible for creating tides (the rise and fall of ______

levels).

a. In1687, Sir Isaac Newton explained that ocean tides happen because of the

gravitational attraction of the ________ and the __________ on the oceans of earth.

i. Newton’s law of universal gravitation states that the gravitational attraction

between two bodies is directly proportional to their masses.

1. So the _______________ something is the ___________ gravitational pull it

will have.

ii. Newton’s law also says that the farther away two objects are, the

______________ the gravitational pull there will be between them.

1. Therefore, the greater the mass of the objects and the closer they are to

each other, the greater the gravitational pull between them.

2. So, the smaller the mass of the object and the farther away they are from

each other, the ___________________ the gravitational pull between them.

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Tides are caused by the gravitational pull of the Moon.

a. The gravitational pull of the Sun also affects tides. Even

though the Sun is 27 million times the size of the Moon, it

has less of an effect on the tides because the Sun is so

much _________________ away from the Earth than the

Moon is.

Tides change in Earth’s oceans approximately every ____ hours.

When the ocean has risen to its highest point, it is called

____________________.

b. When the ocean is at its lowest point, it is called ____________________.

i. The closer a place is to the equator, the ________________ the range will be.

ii. The farther away a place is to the equator, the ______________ the range will be.

The difference between low tide and high tide is called the ______________________________

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For example, the largest tide change occurs in the Bay of Fundy which is in Eastern Canada.

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Types of Tides

1. There are two types of tides on Earth’s surface.

Name Picture Description

Neap Tides are created when the Sun, Earth, and

Moon create a right triangle.

The pull of the Sun counteracts the pull

of the moon.

This type of tide happens twice a

month.

During neap tides, the difference

between high and low tides is very small. There is a

small range.

Spring tides occur when the Earth, Sun, and Moon create a straight

line.

At these times, the high tide is very

high and low tides are very low.

Spring tides are very strong.

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GUIDED PRACTICE

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Directions: For each of the pictures below, decide which term it is describing. Then, write a definition for that term.

Term Picture Definition

INDEPENDENT PRACTICE

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Directions: Match the following terms with the correct definition

1. _____ Neap Tide

2. _____ Tides

3. _____ High Tide

4. _____ Gravity

5. _____ Spring Tide

6. _____ Low Tide

7. _____ Tidal Range

A. The rise and fall of sea levels caused by the combined effects of the rotation of the Earth and the gravitational forces exerted by the Moon and the Sun.

B. When water in the ocean is at its highest

point.

C. The type of tide that occurs when the Sun, Earth, and moon form a right angle. These tides are not very strong.

D. the force of attraction between all masses

in the universe. The larger the mass of an object, the more gravitational pull it will have. This is why all of the planets orbit the Sun.

E. The difference between the highest level

and lowest level of the ocean.

F. When water in the ocean is at its lowest point.

G. The strongest type of tides which occurs when the Sun, Earth, and Moon are in a straight line.

TURN OVER

7th Grade

Science

Unit: Earth, Sun, and Moon Lesson: ESM 9_ Tides 1

Name: _______________________________ Date: October 27, 2016 Homeroom: ________________________

_______/5 = ________%

DNG? Strive Due Date: A B C D F

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Directions: For the following terms, draw a picture to describe it. Then, write a definition to explain the term in words

Term Definition Picture

Neap Tide

Spring Tide

Tidal Range