Understanding Forces and Motion: The Unification Theory

2. Force and the resulting motion Dynamics

3. Unification Theory) Force (Modern)

4. Basic Idea of Forces Push or Pull Influence

5. Types of Influence Contact No contact The push or pull is delivered through contact. Examples are kick, tug, punch, heave, friction, buoyant force, etc. The influence is delivered through space without contact. Examples are magnetic, electric, gravity, etc.

6. Fundamental Forces

7. Note • Electromagnetic force results from the interactions defined by law of poles and law of charges, in the basic level. • Involves the concept that a proton attracts an electron; an electron repels another electron. • Gravitational force is present between matter as a result of their mass. • Greater mass, greater gravity; reduce the distance by half, the force becomes four times as great.

8. Fundamental Forces

9. Note • Strong nuclear force keeps the nucleus together. • Weak nuclear force rips apart nucleons into other particles: beta decay • Involves the release of neutrinos and positrons

12. Fundamental Forces

13. Fundamental Forces

14. http://ngm.nationalgeographic.com/2008/03/god-particle/achenbach-texthttp://ngm.nationalgeographic.com/2008/03/god-particle/achenbach-text

15. Newton’s Laws of Motion Force (Classical)

16. Aristotelian vs. Galilean Motion

17. Aristotelian vs. Galilean Motion

18. Aristotelian Why do objects differ in the way they fall? A rock would fall faster than a leaf, smoke tends to rise and flame always point upward. Generally motion in the vertical Movement of celestial objects: stars, sun, moon, planets. Movement that results from an application of an effort Natural Motion Celestial Motion Violent Motion

22. Aristotelian For Aristotle, the natural tendency of an object is to be in its stable state (stay in its proper hierarchy). For violent motion to persist, a constant effort must be exerted on the object.

23. Galilean Wait, there’s a lot of problems in the natural setting. I will proceed with reason and experiments in my mind.

24. Thought Experiments First Observation: The roughness of the surface (takes something) reduces the speed of the object

25. Thought Experiments First Observation: The roughness of the surface (takes something) reduces the speed of the object

26. Thought Experiments First Observation: The roughness of the surface (takes something) reduces the speed of the object Rough surface Smooth surface

27. Thought Experiments First Observation: The roughness of the surface (takes something) reduces the speed of the object Perfectly smooth surface

28. Thought Experiments Second Observation: The motion of an object is affected by a slope

29. Thought Experiments Third Observation: An object that is not moving will stay in that way unless an effort is exerted on it.

30. Galilean Therefore I can say that no effort is required to keep an object moving. No effort is required to keep it at rest.

31. Galilean That means, the natural tendency of every object is to maintain its state of motion. I will call that property as inertia. Inertia comes from the Latin word iners, which means idle or lazy.

32. Galilean To change state of motion, apply an effort on the object. If it resists, still that is inertia.

33. Galilean To change state of motion, apply an effort on the object. If it resists, still that is inertia.

34. I will make that into a law!! Law of Inertia

36. Born premature, three months after his father’s death, Isaac Newton Sr. • At 3, his mother remarried. He was left at the care of grandparents. “Threatening my father and mother Smith to burn them and the house over them.” • Early part of his education… a school drop out… Asperger syndrome. • At 16, his mother (now widowed again) tried to make a farmer out of him. The legend of the falling apple. • Returned back to school, “motivated partly by revenge to a schoolyard bully, he became the top-ranked student.” • Undistinguished as a Cambridge student. Advancement in mathematics and science and all that came from it, including calculus and mechanics fundamentally grow from seclusion to self-study.

38. Newton’s Three Laws of Motion Law of Inertia – every object maintains its state of motion unless a net force acts on it. Law of Acceleration – the change in the state of motion of an object is directly proportional to the net force acting on it, but inversely proportional to its mass. Law of Interaction – for every action, there is an equal but opposite reaction.

39. Law of inertia – every object tends to maintain its state of motion unless a net force acts on it. So an object maintains its motion if there is no net force or zero total force acting on the object.

40. Review on the concept of resultant vector. What is the resultant of the following vectors: 30 newtons East 50 newtons West 20 newtons East

48. Changes in the state of motion • Change in the direction • Change in the speed • In short, changes in velocity are changes in the state of motion.

49. What happens when you try to change the state of motion of an object?