1. Forces and Motion

2. Click the picture below to get an introduction to forces and motion!

3. Position Position is the location of an object. To describe an object’s position, you say where it is compared with another object. Ex. A tree is ahead of you while running on the playground. As you run past, the tree is behind you. Your position has changed compared with the position of the tree.

4. Reference Point A reference point is any object that is not moving and can be used to describe the position of another object. In the example on the previous slide, the tree is the reference point. Other examples include a desk, a street sign, a line in the road, etc.

5. Distance After choosing a reference point, you can describe an object’s position in terms of distance. Distance is the length of a line between 2 points. Ex. Your chair is 8 cm behind your desk (the reference point). If you move the chair, its distance from the reference point changes.

6. Motion Motion (movement) is a change in position. When an object is in motion, its position changes. An object will be in motion as long as its position keeps changing

7. Measuring Motion You can use linear measurement tools and a stopwatch, watch, or clock to measure motion. For example, you might run 100 feet in 10 seconds. That would mean that you can run 10 feet per second.

8. Describing Motion Motion can be described with words that tell the direction. Direction is the path that a moving object follows. North, South, East, West, right, left, toward, away from, etc.

9. Speed Speed is the measure of how far an object travels in a certain amount of time (how fast or slowly an object moves). Ex. You can ride your bike a distance of 10 kilometers in 1 hour, so your speed is 10 km per hour.

10. Speed To find an objects speed, you must know how far an object moved and how long the object was moving. (Speed = Distance ÷ Time)

11. Graphing Motion You can measure the motion of an object by measuring the distance it travels in a certain amount of time. When you measure those factors, you are collecting data (pieces of information including words and numbers).

12. Data Table You can organize the data you collect with a data table. Once you have recorded your data on a data table, a line graph can be made from that data. A line graph shows data as a line on a grid. Distance (miles) Time (hours)

13. Line Graph The period of time that an object travels goes along the x-axis (horizontal). The distance traveled by an object goes along the y-axis (vertical). This is called a distance- time graph. If the line on the graph is straight, the speed of the object remained constant. Distance (miles) Time (hours) X-axis Y-axis

14. Constant Motion and Stopped Motion You can look at a distance-time graph and tell what type of motion is taking place. In the line graphs on the previous slides, constant motion is taking place, meaning that the car is moving the same speed the entire time. Some distance-time graphs show stopped motion, meaning that the object was moving, but stopped for some reason. Notice that the distance is increasing as the time passes until you get to 5 seconds. Time continues to pass but no distance is added.

15. Faster Motion The steeper the slope is on the distance-time graph, the faster the objects speed is. Look at the following graph for example: Notice that the object moves about 3 meters per second until the 30 second mark. The object stops moving for 20 seconds, then begins moving again at 50 seconds, but at a faster rate of 15 meters per second. You can see that the line has a steeper slope.

16. Force and Motion R emember that motion is a change in an object’s position. How do you make things move? To make things move, you apply a force (a push or a pull). When you push an object, you exert a force away from you. When you pull an object, you exert a force toward you. A force can cause an object to move or change the way an object moves after it is already moving. A force can also change the speed of an object. Objects move in the same direction as the force that acts on it. Force of kick Motion of ball https://www.brainpop.com/science/motionsforcesandtime/force/

17. Mass and Motion An object’s motion also depends on its mass (the amount of matter that makes up an object). An object’s mass determines how much a force will change its motion. For example, it is harder to push a shopping cart full of groceries than it is to push an empty shopping cart.

18. Gravity Gravity is a force that pulls object toward each other. It can attract objects toward each other even if they do not touch. Any object with mass exerts a force of gravity. The more mass an object has, the greater its pull of gravity. The force of gravity depends on mass and distance. https://www.brainpop.com/science/motionsfo rcesandtime/gravity/

19. Mass and Gravity Objects with more mass exert a greater force of gravity. For example, think about a coconut and the Earth. Both objects pull on each other because they both have mass, but Earth’s mass is much greater, meaning that its force of gravity is greater. Earth’s gravity pulls the coconut down to the ground. * Disclaimer: Coconuts don’t actually have faces. *

20. Distance and Gravity Distance also determines the force of gravity between two objects. The closer together 2 objects are, the greater the force of gravity between them. The farther apart 2 objects are, the weaker the force of gravity is between them. Less gravity More gravity

21. Friction Friction is a force that acts between surfaces that touch each other. Friction tends to slow an object’s motion. For example if you push a ball across the carpet, friction between the carpet and ball slows the ball’s motion. Different surfaces affect the amount of friction produced. Rougher surfaces tend to have more friction and smoother surfaces tend to have less friction.

22. Air Resistance An object can encounter friction as it moves through the air. This is called air resistance. Air resistance acts against the pull of gravity to slow an objects motion.

23. Newton’s Laws of Motion Click the links below to learn more about Newton’s Laws of Motion: – https://www.brainpop.com/science/motionsforcesandti me/newtonslawsofmotion/ https://www.brainpop.com/science/motionsforcesandti me/newtonslawsofmotion/ – http://studyjams.scholastic.com/studyjams/jams/scienc e/forces-and-motion/inertia.htm http://studyjams.scholastic.com/studyjams/jams/scienc e/forces-and-motion/inertia.htm – http://studyjams.scholastic.com/studyjams/jams/scienc e/forces-and-motion/acceleration.htm http://studyjams.scholastic.com/studyjams/jams/scienc e/forces-and-motion/acceleration.htm – http://studyjams.scholastic.com/studyjams/jams/scienc e/forces-and-motion/action-and-reaction.htm http://studyjams.scholastic.com/studyjams/jams/scienc e/forces-and-motion/action-and-reaction.htm

24. Real World Science: Forces http://ottosonmiddleschoolteched.weebly.com/real -world-science---forces-and-newtons-laws.html http://ottosonmiddleschoolteched.weebly.com/real -world-science---forces-and-newtons-laws.html

25. Review Videos Bill Nye the Science Guy: Motion

26. Review Games http://interactivesites.weebly.com/physics- and-motion.html http://interactivesites.weebly.com/physics- and-motion.html