newton's laws of motion: teks 8.6c to the teacher: this cpo science powerpoint presentation is...

Newton's Laws of Motion: TEKS 8.6C

To the teacher:• This CPO Science PowerPoint presentation is designed to guide you

through the process of presenting the lesson to your students. The presentation uses a 5-E teaching model: Engage, Explore, Explain, Elaborate, and Evaluate.

• The PowerPoint Slide notes indicate where you may want to bring in various lesson elements such as quizzes, readings, investigations, animations, and practice materials. Additional science background information is provided in the slide notes where appropriate. You can view these notes by selecting “View,” then “Normal.” You will see the notes pane at the bottom of the PowerPoint workspace. Additionally, the slide notes are available as a separate document, accessible from the lesson home page.

• The slides that follow are intended for classroom use.


Amusement park physics• Have you ever wondered

why it feels like you’re being lifted out of your seat as you start to go down a big hill on a roller coaster?

• Have you ever wanted to predict which way bumper cars will move after colliding?

• Newton’s laws can help you unlock the secrets of amusement park physics. You will find the answers to these questions and more in the Newton’s Laws of Motion module.


Time to investigate!• Complete the lesson

investigation:– Newton’s Second Law

• How do force and mass affectacceleration?


Newton’s law of inertia• When the net force is zero,

objects at rest stay at rest and objects in motion keep moving with the same speed and direction.

• A net force is required to speed up an object. The force of the club provides the net force that moves the golf ball.

• A net force is needed to slow down the golf ball, too. When the club is no longer acting on the ball, friction supplies the net force.


What is inertia?• Newton’s first law is often called

the “law of inertia” because inertia is the property of an object that resists motion.

• Inertia comes from mass. Objects with more mass have more inertia.

• If you apply the same force to a bowling ball and a golf ball, which accelerates faster?

• The golf ball accelerates faster. The bowling ball’s mass is 100 times the golf ball’s mass. The bowling ball is more resistant to changes in motion.


Application: Seat Belts• Why are seat belts important?• Imagine you’re riding unbelted in

a car going 55 km/h (35 mph). If the car crashes, your body will continue to move forward at 55 km/h until acted on by a net force.

• The car’s interior provides the stopping force. Your body collides with the dashboard, or possibly the windshield, at 55 km/h.

• A seat belt provides the net force that stops you before you collide with the car’s interior.


Newton’s law of force and acceleration

• The acceleration caused by a force is proportional to force and inversely proportional to mass.


Application: bumper cars• Bumper cars are powered by

electric motors. You can assume that all of the bumper cars in an arena have similar motors that produce about the same amount of force.

• A car driven by a seven-year-old girl bumps into the arena wall. Another car, driven by her dad, bumps into the same wall at the same speed. Which car experiences the greater backward acceleration? Why?


Newton’s law of action-reaction• Every action force creates a

reaction force that is equal in strength and opposite in direction.

• Think about the skateboard: You push on the ground. The reaction force is the ground pushing on you!

• The reaction force propels you forward.


Working with action-reaction pairs

• Both action and reaction forces are always there whenever any force appears.

• They always have the same strength.

• They always act in opposite directions.• They always act on different objects.• Both are real forces and can cause changes in motion.


Application: rocket launches

• What happens when you blow up and then release a party balloon? It darts around the room! The action is the air moving out. The reaction is the balloon’s movement in the opposite direction.

• A rocket works on the same principle. The engine forces material out of the nozzle in one direction, causing the rocket to move in the opposite direction.


Time for Practice!

• Complete the lesson practice activity:– Applying Newton’s Laws of Motion


Show what you know!

• Try the lesson’s interactive quiz, or complete a quiz that your teacher can print out for you.

• Hint: – You might want to review your lesson reading piece one

more time before trying the quiz.

newton's laws of motion: teks 8.6c to the teacher: this cpo science powerpoint presentation is...

Documents

net force

c newtons law of force

newtons laws of motion

c newtons law of inertia

stopping force

powerpoint slide notes

c application

bumper cars bumper cars