1. Wednesday February 1st Sir Isaac Newton’s Laws: First and Second Laws of Motion

2. Okay! So what are we doing today? Content Objective: Students will be able to summarize the three laws of motion. Literacy Objective: Students will be able to define inertia as the tendency of an object to resist a change in its motion

3. First Law of Motion The First Law of Motion states that if the net force acting on an object is zero, the object doesn’t change its motion – If it’s at rest – it stays at rest – If it’s moving – it keeps moving Only Unbalanced forces change an object’s velocity

4. We basically knew all that already!

6. Does anyone here HATE change? You like things the way they are and you don’t want to change them? In humans this is called being stubborn In objects this is called inertia

7. Inertia Inertia is the tendency of an object to resist change in its motion ALL OBJECTS HAVE INERTIA, whether they are moving or not Inertia means objects hate change The heavier and object, the more it resists change – Imagine stopping a sumo wrestler running at you vs. stopping a horse jockey running at you

8. What happens in a car crash? Let’s test it out with my dear friend, Winnie the Pooh!

9. Second Law of Motion Second Law of Motion – the acceleration of an object is in the same direction as the net force on the object – (whichever way the net force is pointing, that’s the direction the object moves) Force = Mass * Acceleration (F = ma)

10. Third Law of Motion Third Law of Motion: for every action there is an opposite and equal reaction A good example is jumping on a trampoline http://www.youtube.com/watch?v=TK27akn WVI4 http://www.youtube.com/watch?v=TK27akn WVI4

11. So let’s review the 3 laws: First Law: An object in motion tends to stay in motion, an objet at rest tends to stay at rest (unless acted upon by an unbalanced force) Second Law: F=m*a, i.e. it takes more force to move a heavier object the same distance Third Law: For every action there is an opposite and equal reaction

12. Visual Review of 3 Laws http://www.youtube.com/watch?v=cP0Bb3W XJ_k http://www.youtube.com/watch?v=cP0Bb3W XJ_k