# Newtons Laws of Motion Chapter 2 Section 2

• Slides: 13

Newton’s Laws of Motion Chapter 2 Section 2 http: //www. youtube. com/watch? v=Pk. AO 8 F-Tm-w

Newton’s 3 Laws State 1. An object at rest remains at rest and an object in motion remains in motion at a constant speed and in a straight line unless acted on by an unbalanced force. 2. The acceleration of an object depends on the mass of an object and the amount of force applied. 3. Whenever one object exerts a force on a second object the second object exerts an equal and opposite for on the first.

Let’s Break Down the First Law • Objects At Rest – Remains at Rest unless affected by an unbalanced force. – For example a soccer ball sitting in the grass will not move unless you apply a force- kicking it • Objects In Motion – Objects moving at a certain velocity do not change unless an unbalance force acts on it. – For example- Friction on a sliding box slowing its motion or a ball being kicked changing its direction

Law of Inertia • Newton’s First Law is often referred to as the law of Inertia. • Inertia is the idea that an object resists any change in motion. So basically an object does not like change any more than you or I. • More massive objects have more inertia than less massive objects. This is why it is easier to stop a match box car verse a large Tonka truck.

How does our knowledge of Newton’s First Law of Motion help us? Engineers use Newton’s Laws to Build our cars safer. Watch the attached video and answer the question. http: //www. youtube. com/watch? v=IMNf. Vo. Pe 694 Name two devices in cars that are made keep us safe and lessen the effects of the Law of Inertia. Explain how they help people prevent injuries during a car crash?

Let’s Review Newton’s First Law • Please watch this video http: //www. youtube. com/watch? v=ii. Uz. RKW_4 lw • Why the string on top of the ball when it is pulled down slowly but breaks on top of the ball down when the ball is pulled quickly?

Newton’s Second Law of Motion • This law is most commonly recognized by the formula F=MA • Acceleration Depends on Mass – It takes a small force to cause a less massive object to move than a more massive one – Which would be easier to move? Explain why?

– Watch this video and see if what you said agrees with this scientist’s answer. http: //www. youtube. com/watch? v=iw. P 4 he. WDhv w • Acceleration Depends on Force – The more force you apply the more an object will accelerate. – Consider throwing a baseball. Can you cause it to move faster if you throw it harder? – http: //www. youtube. com/watch? v=n. JTKi. S 444 BQ

Newton’s Third Law of Motion • This law is often thought of as the actionreaction law because it states for every action there is a equal and opposite reaction. • Watch this video to see how most people apply this law. http: //www. youtube. com/watch? v=8 b. Td. Mm. NZm 2 M

Paired forces • When we discuss that forces act in pair we do not mean two forces act on a single object. Instead what we say is each object applies a force on the other.

Describe the forces responsible for liftoff when a rocket is launched.

• The effect of the forces are not always easy to see here on Earth. • Watch the video to see how these effects that may not be easily viewed on earth can be see in space due to the “weightlessness” of the astronauts. http: //www. youtube. com/watch? v=c. P 0 Bb 3 WXJ_k

Let’s Use the X Game Events To Help Us Review • Watch these three videos. http: //www. youtube. com/watch? v=F 9 COt. JBBzhk http: //www. youtube. com/watch? v=xy 3 x. LTe. Wgpg http: //www. youtube. com/watch? v=B_x. Ffg 6 e. TFs • Watching the X games will never be the same now that you understand how Newton’s Laws applied to the tricks you see.