1. Forces and Motion 2013 M.B. Pardington, BPS

2. A force is a… PUSHPULL

3. A force can change the motion of an object. SPEED DIRECTION

4. A force can change the motion of an object.

5. An additional force in the same direction increases the speed of the object. Push Push + Push

6. An additional force in the same direction increases the speed of the object. Push Push + Pull

7. An additional force in the same direction increases the speed of the object. Pull Pull + Pull

8. Opposing forces of equal magnitude acting on an object produce no change in motion. 5 N vs. 5 N Cart doesn’t move.

9. Opposing forces of equal magnitude acting on an object produce no change in motion. 5 N vs. 5 N Cart doesn’t move.

10. Opposing forces of unequal magnitude acting on an object result in a change in motion. 3 N Pull + 5 N Push NET FORCE 2 N PUSH to the RIGHT

11. A change in motion is described as a change in speed and/or direction of an object. 3 N Pull + 5 N Push NET FORCE 2 N PUSH to the RIGHT

12. BALANCED FORCE A force must be balanced in order to achieve constant speed.

13. UNBALANCED FORCE A force must be unbalanced (nonzero net force) in order for an object to change speed and/or direction. 20 N 40 N

14. UNBALANCED FORCE A force must be unbalanced (nonzero net force) in order for an object to change speed and/or direction. 20 N 50 N 30 N

15. UNBALANCED FORCE A change in the mass of the object will result in a change in speed and/or direction of the object. Compare these 3 carts.

16. UNBALANCED FORCE A change in the mass of the object will result in a change in speed and/or direction of the object. Compare these 3 carts.

17. UNBALANCED FORCE A change in the mass of the object will result in a change in speed and/or direction of the object. Compare these 3 carts.

18. Speed Speed is the ratio of distance covered per unit of time. Speed = distance / time The cart moved 6 meters per 3 seconds

19. Speed The cart moved 6 meters per 3 seconds Mathematically, that’s 6 / 3 or 6 ÷ 3 which equals 2. So, the cart moved 2 meters per second or 2 m/sec

20. FORCE CONTACT NON- CONTACT

21. Contact Force

22. contact force A contact force is a push or pull that directly touches the object..

23. Friction Friction is a contact force exerted between objects such as: AIROBJECTS WATER

24. Non-Contact Forces GRAVITY MAGNETISM ELECTRICAL CHARGES

25. Non-Contact Forces These are pushes and pulls from a distance.

26. Gravity Gravity For objects on Earth, the pull of the Earth is the strongest force acting on them. Gravity is a force of attraction between any mass and the matter near it. The larger the mass of an object, the greater the gravitational force it exerts on other objects. For objects on Earth, the pull of the Earth is the strongest force acting on them.

27. Gravity “Jupiter is the most massive planet in our Solar System and; therefore, the gravity of Jupiter is the most intense in the Solar system. Its gravitational pull is 2.5 times what is here on Earth.” http://www.universetoday.com/15110/gravity-of-jupiter/

28. Gravity

29. Magnetism N NSS Here are “like” charges. Are they showing an attraction or are they repelling?

30. Magnetism NNSS They are repelling. Magnetic Repulsion

31. Magnetism NNSS Here are “unlike” charges. Are they showing an attraction or are they repelling?

32. Magnetism NNSS They are showing an attraction. Magnetic Attraction

33. Magnetism NNSS The attracting and repelling magnetic forces illustrate non-contact forces. They pull and push without contact. N NSS

34. Electrical Charges The attracting and repelling electrical forces illustrated in the wind sock demonstration show non-contact forces. They push without contact.

35. Bibliography http://powerup.ukpowernetworks.co.uk/media/22576/78.jpg http://www.clipart.dk.co.uk/DKImages/science/image_science010.jpg http://www.clipart.dk.co.uk/DKImages/science/image_science009.jpg http://www.universetoday.com/15110/gravity-of-jupiter/ http://www.mikecurtis.org.uk/images/friction.jpg http://lvp.lockyersmid.dorset.sch.uk/pluginfile.php/3230/mod_resource/content/0/content/pictures/physical/keyideas/phpkey0005.jpg http://www.united-states-flag.com/media/catalog/product/cache/1/image/9df78eab33525d08d6e5fb8d27136e95/F/L/FLGBDEC1000003637_- 00_st-patricks-wind-sock_4.jpg