Newton / 1st Law of Motion October 22, 2012

Sir Isaac Newton One of the most important scientists… EVER!!! He lived from 1642 to 1727 He came up with 3 LAWS OF MOTION as well as the universal law of gravitation We’ll be talking about the three laws of motion starting today We’ll come back to the universal law of gravitation after Thanksgiving Even though his discoveries are about 300 years old, they are still used today!

Before we talk about Newton’s first law… Each group will get a cup, a card, and a penny Put the card flat on top of the cup and the penny on top of the card Your group has to figure out how to remove the card so that the penny falls directly into the cup, but: No part of the card can rise above its initial location Pretend like your fingers have ink on them, no fingerprints should be on the card (you can hold the cup if you want, though) You have 2 minutes to discuss what your strategy will be with your group and write it down in your notes Then you have 3 minutes with the materials to see if you can figure out how to actually do it

Newton’s First Law of Motion Newton’s first law of motion says an object at rest stays at rest and an object in motion stays in motion with the same speed and same direction unless acted on by an unbalanced force This is also called inertia Inertia is an objects resistance to change it’s motion An object has a constant velocity unless there is an unbalanced force acting on it Acceleration requires an unbalanced force

What is a force? A force is some type of push or pull Some forces are through direct contact of objects For example, if I shove a chair, then I come in contact with the chair Some forces don’t deal with direct contact For example, gravity pulls objects towards the earth’s center even when an object isn’t in contact with the earth

Table Cloth Demo 1. Is it possible to remove the tablecloth without significantly moving the books lying on it? 2. Is it possible to remove the tablecloth without significantly moving the pieces of paper lying on top of it? QUESTIONS 1. Why don't the books fly off the table when Ms. K. pulls the tablecloth out the first time? 2. Explain the difference between Activity 1 (books on the table) and Activity 2 (paper on the table).

Inertia depends on mass Inertia depends on an object’s mass Mass is just how much stuff makes up an object If an object has more mass, it takes more to make it change it’s motion More mass means more inertia If an object has less mass, it takes less to make it change its motion Less mass means less inertia We’ll talk more about this more in later classes

Table Cloth: Extra Large http://www.youtube.com/watch?v=-cM9S2AzU28

Homework Explanation Drawing/Description The skateboarder goes flying off his skateboard because he is an object in motion that wants to stay in motion, and his inertia carries him forward! A skateboarder flies off his skateboard when he hits a rock. Have students create a foldable on which to make these examples. They should have at least two per law. Use this page to make your own example. Come up with two of your own examples. 1) Draw a picture and describe the situation 2) Explain how the situation relates to Newton’s first law of motion