Newton’s First Law of Motion - Inertia Unit 3 Newton’s First Law of Motion - Inertia

Section 3-1 Evolution of Motion Aristotle: 380-320 BC Natural Motion Objects have natural resting places Heavy Stuff Falling, Light stuff Rising, Circular Motion Violent Motion Forced Motion from pushing or pulling A force is needed to make an object move from its natural rest.

Section 3-1 Evolution of Motion Evolution of Forced Motion Copernicus 1473-1543 Described Earth’s Motion Earth is Moving Only way to Explain the Motion of Planets Contradicts Aristotle’s Natural Rest

Section 3-1 Evolution of Motion Evolution of Forced Motion Galileo 1564 -1642 Forces aren’t needed to keep things moving Friction makes things slow down Gravity changes the speed of objects

Section 3-1 Evolution of Motion Galileo answer How things moved, not why!

Section 3-1 Evolution of Motion Galileo answer How things moved, not why!

Section 3-1 Evolution of Motion Inertia: A characteristic of an object that resists any change in motion. Complete the venn diagram comparing and contrasting Aristotle and Galileo’s ideas on motion. [#2 on Checklist]

Section 3-1 Evolution of Motion Evolution of Forced Motion Isaac Newton 1642 -1726 Published a paper that defined the Laws of Motion First Law - Inertia Second Law – Acceleration Third Law – Action & Reactions

Section 3-1 Evolution of Motion Time Line 400 BC 300 200 100 100 AD 400 500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 Aristotle Copernicus Galileo Newton Present Day

Section 3-1 Evolution of Motion Concept Questions to Answer in Small Groups A ball is rolled across a counter top and rolls slowly to a stop. How would Aristotle interpret this behavior? How should you interpret this behavior?

Section 3-1 Quiz Quiz will be on : _____________________ Topics you need to Study: History of Motion – Which Scientist were responsible for Specific Ideas Vocab – Inertia, Force & Friction

Section 3-2 Newton’s 1st Law Broken Brick - Demonstration & Notes Sketch Description of Observation Initial Explanation of Observation Final Explanation of Observation

Section 3-2 Newton’s 1st Law Newton’s 1st Law: Every object continues in a state of rest, or of motion in a straight line at constant speed, unless it is compelled to change that state by forces exerted upon it. WHAT DOES THIS MEAN!!!!!

Section 3-2 Newton’s 1st Law

Section 3-2 Newton’s 1st Law Concept Questions to Answer in Small Groups

Section 3-2 Newton’s 1st Law Concept Questions to Answer in Small Groups

Section 3-2 Newton’s 1st Law Inertia Review – Objects don’t like to change their motion. Their “Laziness” Which of the following objects would be the hardest to kick? A. An Empty Can b. A can filled with water C. A can filled with Lead

Section 3-2 Newton’s 1st Law The amount of inertia in an object depends on its mass.

Section 3-2 Newton’s 1st Law Can you use Newton’s 1st law of motion to explain what has happened in the pictures below.

Section 3-2 Newton’s 1st Law Misconception ALERT!! Don’t confuse size (volume) with mass.

Section 3-2 Newton’s 1st Law Comparing Mass and Weight Mass Weight The amount of Matter in an object. The force of gravity on an object (how hard the object is pulled down) S.I. Unit = Kilograms S.I. Unit = Newtons Measured with Balance Measured with Spring Scale Same on any planet or in deep space. Changes based on the planets gravity and is Zero in deep space. A Calculated Value: W = m · g

Section 3-2 Newton’s 1st Law Concept Questions to Answer in Small Groups Compare a 2-kg iron block to a1-kg iron block. Does it have twice the mass? Does it have twice the inertia? Does it have twice the volume? Does it have twice the weight on Earth?

Section 3-2 Newton’s 1st Law Concept Questions to Answer in Small Groups Compare a 2-kg bunch of Bananas to a 1 kg loaf of bread. Does it have twice the mass? Does it have twice the inertia? Does it have twice the volume? Does it have twice the weight on Earth?

Section 3-2 Newton’s 1st Law Read Text book Page 55 Summarize the important information in your notebook. Try and Guess the Notes.

Section 3-2 Newton’s 1st Law Inertial Reference Frame Video

Section 3-2 Newton’s 1st Law Concept-Development Practice Page 4-1 [#6 on Checklist] Complete the Front and Back

Section 3-2 Quiz Quiz will be on : _____________________ Topics you need to Study: Newton’s 1st Law of Motion Mass vs. volume vs. Weight

Book Assignment Pages 56 & 57 6 – 14, 21 – 25, and 26 – 30.

Section 3-3 Net Force Forces are Vectors

Section 3-3 Net Force Some Common Forces we will measure and investigate in Class. Applied Forces Weight Normal Force

Section 3-3 Net Force More than one force can act on an object at a time. Net Force: The combination of all the forces acting on an object.

Section 3-3 Net Force Equilibrium is when the net force on an object equals zero.

Section 3-3 Net Force Equilibrium = static Motion = Balanced Forces Misconception Alert!!! Can an object be moving and still have a net force of zero? If an object is in equilibrium, does it mean that no forces are acting on it? Can an object be in equilibrium and have a non-zero net force?

Section 3-3 Net Force Understanding Equilibrium If the net force is zero, how much does each string need to pull up on the block?

Section 3-3 Net Force Understanding Equilibrium What happens if the strings aren’t vertical?

Section 3-3 Net Force Concept Questions to Answer in Small Groups Explain why a rope could be used to safely hang a tire swing, but might break if used as a clothes line and you hang on it?

Section 3-3 Net Force Concept-Development Practice Page 4-2 [#9 on Checklist] Complete the Front and Back

Section 3-3 Net Force Calculating Net Force Net force is a result of all the forces acting on an object. Calculate Net Force like any other resultant vector.

Section 3-3 Net Force Determine the Net force on the mass for each scenario.

Section 3-3 Net Force Find the net force on the box. 4 N 2 N 5 N

Section 3-3 Net Force Concept-Development Practice Page 4-2 [#10 on Checklist] Complete the Front and Back

Section 3-3 Quiz Quiz will be on : _____________________ Topics you need to Study: Motion of Objects when in equillibrium Calculating Net Force

Unit 3 Quick VideoReview Flipping Physics - Introduction to Newton’s First Law of Motion