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Physics Core/AP 1 and 2

Chapter 4: 5-7 Assignment

Course Materials are always under revision! Weblecture content may change anytime prior to two weeks before scheduled chat session for content.

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Physics Chapter 4: 5-7: Newton's Third Law of Motion and Weight


Reading Preparation

Text Reading: Giancoli, Physics - Principles with Applications, Chapter 4: Sections 5-7

Study Points

Key Equations

Gravitational force: F =   m g

Normal force (note that if the angle is 90°, cos θ = 1 and normal force is equal but opposite to gravitaitonal force): F   N =   mg   cos   θ

Force due to friction: F f =   μ F N    =    μ mg   cos   θ

Web Lecture

Read the following weblecture before chat: Vector Forces and Newton's Laws

Study Activity

The website below will either download a Java applet to your computer or run the applet in place, depending on how your browser is configured. You will need Java installed to run the applet locally on your computer.

The "friction" simulation will download to a java program, which you may be able to run if you have Java libraries installed on your computer.

Forces and Motion
Click to Run

Explore the forces at work when you try to push a filing cabinet. Create an applied force and see the resulting friction force and total force acting on the cabinet. Charts show the forces, position, velocity, and acceleration vs. time. View a Free Body Diagram of all the forces (including gravitational and normal forces).

Physics simulation Java Applets are the product of the PHET Interactive Simulations project at the University of Colorado, Boulder.

Chat Preparation Activities

Chapter Quiz

Lab Work

If you want lab credit for this course, you must complete at least 12 labs (honors course) or 18 labs (AP students). One or more lab exercises are posted for each chapter as part of the homework assignment. We will be reviewing lab work at regular intervals, so do not get behind!