Unit 4. More Topic in Forces

This unit focus on various additional topics in forces including inclined planes, adding forces in two dimensions, friction, universal gravity and circular motion.  

Goals
• Be able to add forces in two dimensions.
• Determine the normal force, and the parallel and perpendicular components of gravity for inclined plane problems and solve for acceleration.

• Calculate the frictional force when given the coefficient of friction and vice versa.
• State and apply equations for centripetal acceleration and force.

• Distinguish between the centripetal force and the fictitious centrifugal force.
• Analyze examples of circular motion in terms of Newton's three laws of motion.

Use Newton's Law of Universal Gravitation alone and in conjunction with circular motion equations to describe the motion and forces of planets.



Important Dates
Friction Lab : due Tues Dec. 4.

Gravity Mini Lab: due Nov 20
Homework: Nov. 5, Nov. 28  and Dec. 10, all at 10:00 pm
Unit Test: Dec. 13

This unit corresponds to parts of chapters 6, and 7 in the book.

Review for Forces Test.

To review:
Go over the unit goals in the previous post.
Use the physics classroom for extra reading and practice questions.  http://www.physicsclassroom.com/reviews/newtlaws

Do the review sheet from class and check your answers with the key.
The multiple choice answers for the last page are missing.  Here they are
1. a;  2. a, b;  3. d, e;  4. a;  5. c, f;  6. c, f;  7. c;  8. a

Unit 3 Overview - Newton's Law

Goals

1.  Draw Force Vectors.
2.  Calculate Weight.
3.  Solve Problems with Net Force.
4.  Know that when an object is at rest or moving with constant velocity that Fnet = 0 and all of the forces are balanced.
5.  Understand what terminal velocity is and how it is reached.
6.  Be able to explain why all objects in freefall have an acceleration of 9.8 m/s2
7.  Understand that forces are interactions between two things and that each object exerts an equal and opposite force on the other.
8.  Know Newton’s Three Laws of Motion by name.

In general, understand Newton’s 3 laws and apply them to explain motion.

 Lab Due Date: Oct. 27

 Homework due in the evening of Oct. 23, and Oct. 31

Test Date Nov. 2 

Answers to the Review Questions and even more practice with answers.

Vectors in 2 dimensions practice
answers are on the last page

Review Answers 2013

Vector Unit Overview

Unit Goals:
1. Know that perpendicular vectors are independent
2. Add vectors graphically with parallelogram and head to tail methods.
3. Use trig and Pythagorean theorem to find resultant.
4. Break vectors into perpendicular components graphically and with trig.
5. Solve motion problems in 2D.

Covers Sections 4.1, 4,2 and 7,2 or continue reading from the links on the physics tutorial website http://www.physicsclassroom.com/Class/vectors/


Homework Sun 10/1

                  Sun 10/8

Test Tuesday 10/10

No Lab Reports this Unit

Motion in 2 Dimensions Pre Reading and Questions

Please read the following two pages at the Physics Classroom Website.
http://www.physicsclassroom.com/class/vectors/Lesson-1/Vectors-and-Direction
and
http://www.physicsclassroom.com/class/vectors/Lesson-1/Vector-Addition

Then do the new short assignment at the university of Texas.
https://quest.cns.utexas.edu/
The assignment is due Sunday night.

Review answer key

There are actually two problems with this version of the key that I fixed for class.  Problem 1, the second point is 7s, 50m.  This makes the slope 5m/s.  In problem 6 on the first page the acceleration should be negative.  I fix this later in the solution.

Kinematics Review Key 2013