2. Unit 5 Lesson 5 Gravity and Motion
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3. Unit 5 Lesson 5 Gravity and Motion
Florida Benchmarks
SC.6.P.13.1 Investigate and describe types of forces including contact forces and forces acting at a distance, such as electrical, magnetic, and gravitational.
SC.6.P.13.2 Explore the Law of Gravity by recognizing that every object exerts gravitational force on every other object and that the force depends on how much mass the objects have and how far apart they are.
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4. Down to Earth What is gravity?
Unit 5 Lesson 5 Gravity and Motion
Down to Earth
What is gravity?
Gravity is a noncontact force of attraction between objects due to their mass.
All objects on Earth fall at the same rate once air resistance and other factors are removed.
Force = mass × acceleration due to gravity (F = mg), where g is about 9.8 m/s2.
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5. Unit 5 Lesson 5 Gravity and Motion
What is gravity?
All matter has mass, so all matter is affected by gravity.
All objects experience gravitational attraction to all other objects.
Earth and other planets are round because of gravity.
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6. Unit 5 Lesson 5 Gravity and Motion
What is gravity?
Some objects in space are not round because they are too small for gravity to shape them into a sphere.
The paths of the planets, the sun, and our galaxy are determined by gravity.
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7. A Weighty Issue What determines the force of gravity?
Unit 5 Lesson 5 Gravity and Motion
A Weighty Issue
What determines the force of gravity?
The law of universal gravitation states that all objects attract each other through gravitational force.
The strength of the gravitational force is related to the mass of the objects and the distance between them.
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8. What determines the force of gravity?
Unit 5 Lesson 5 Gravity and Motion
What determines the force of gravity?
Gravitational force between two objects increases as the distance between their centers decreases.
Gravitational force between two objects increases as their masses increases.
Objects with greater mass have more attraction between them than objects with smaller mass.
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9. Don’t Bring Me DOWN How does gravity keep objects in orbit?
Unit 5 Lesson 5 Gravity and Motion
Don’t Bring Me DOWN
How does gravity keep objects in orbit?
Free fall is when gravity is pulling an object down and no other forces are acting on it.
An object is in orbit when it travels around another object in space.
Forward motion and free-fall motion combine to cause orbiting.
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10. How does gravity keep objects in orbit?
Unit 5 Lesson 5 Gravity and Motion
How does gravity keep objects in orbit?
Spacecraft, satellites, the moon, planets, and stars all complete orbits.
Any object in curved motion is constantly changing direction.
Gravity pulls objects toward the center of an orbital path.
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11. How does gravity keep objects in orbit?
Unit 5 Lesson 5 Gravity and Motion
How does gravity keep objects in orbit?
Describe how forces keep the moon in orbit around Earth.
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