1. Unit 11 Lesson 1 What Is Motion?
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2. How can you tell something is moving?
Unit 11 Lesson 1 What Is Motion?
How can you tell something is moving?
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3. Unit 11 Lesson 1 What Is Motion?
Twisting and Turning
Position is the location of an object in relation to a nearby object or place. The second object or place is called a reference point.
An object that moves has motion. Motion is a change in position.
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4. Twisting and Turning Unit 11 Lesson 1 What Is Motion? 4
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5. Twisting and Turning Unit 11 Lesson 1 What Is Motion? 5
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6. Unit 11 Lesson 1 What Is Motion?
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7. Unit 11 Lesson 1 What Is Motion?
Frame of Reference
You know something is moving if its position changes against a background .
The background in called frame of reference.
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8. Where Is It? Unit 11 Lesson 1 What Is Motion? 8
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9. Unit 11 Lesson 1 What Is Motion?
Fast or Slow?
One way to describe motion is to find speed, or how fast or slow something is moving.
Speed tells you how the position of an object changes during a certain amount of time.
You can measure time in hours (hr) minutes (min) or seconds (sec).
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10. Unit 11 Lesson 1 What Is Motion?
Fast or Slow?
To find an object’s speed, divide the distance the object travels by the time it took to travel that distance.
If you walk 30 meters (m) in 15 seconds ( sec) your speed is ???
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11. Fast or Slow? Unit 11 Lesson 1 What Is Motion? 11
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12. Unit 11 Lesson 1 What Is Motion?
Fast or Slow?
Velocity is the speed of an object in a particular direction.
If your speed is 2 m/sec then your velocity is 2 m/sec, east.
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13. Fast or Slow? Unit 11 Lesson 1 What Is Motion? 13
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14. Unit 11 Lesson 1 What Is Motion?
Pushes and Pulls
A push or pull is a force. A force can change an object’s speed or direction.
Gravity is a force that pulls objects down to Earth.
Friction is a force that acts directly against the direction of motion. Friction can slow things down or make them stop.
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15. Pushes and Pulls Unit 11 Lesson 1 What Is Motion? 15
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16. Pushes and Pulls Unit 11 Lesson 1 What Is Motion? 16
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17. Unit 11 Lesson 1 What Is Motion?
Changing It Up
The gas pedal on a car is called an accelerator. The brakes and steering wheel are also accelerators.
You may hear people say that a car is accelerating when it speeds up.
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18. Changing It Up Acceleration is any change in velocity.
Unit 11 Lesson 1 What Is Motion?
Changing It Up
Acceleration is any change in velocity.
An object accelerates if it speeds up, slows down, or changes direction.
If a force pushing against an object in one direction is greater than a force pushing in the opposite direction, the object will accelerate.
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19. Changing It Up Unit 11 Lesson 1 What Is Motion? 19
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20. Changing It Up Unit 11 Lesson 1 What Is Motion? 20
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21. Changing It Up Unit 11 Lesson 1 What Is Motion? 21
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22. Unit 11 Lesson 1 What Is Motion?
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