multiple Body Problems

UNIT:Dynamics
Mechanical Systems

• Draw a picture with all the forces acting upon it.  (F.B.D)

• Assign a direction to be positive.  (F.O.R) + usually     preferred  for the direction of acceleration.

• Write a relationship for the sum of the forces in the x and y direction
• Substitute and solve for unknown terms this may need to be done repeatedly

• In a system that includes Multiple Bodies
•   write the equation for each body
•   write an equation for the combined system

* Note:  If objects are bound, they must share the same  motion but not necessarily the same force.

TODAYS NOTES HW

UNIT: Dynamics
DAY: 36
ACTIVITY:Friction

 NOTES


HW.  CALCULATE THE acceleration of the object if it is sliding down the ramp

P:Calculate the acceleration if the object is sliding up the ramp>

• Q:  Could it be sliding up the ramp at constant velocity?  EXPLAIN.

UNIT: Dynamics
DAY:33
ACTIVITY:  HW

COMPLETE at least 5 points on section 4.10 Problems at end of Chapter
A point = # stars +1
Example
**= 2 stars = 2+1=3 points

FLAT EARTH GRAVITATION

UNIT:Dynamics
DAY:32
ACTIVITY:Forces


Universal Law of Gravitation
The radius of the Earth!

Measurement of the Earth's circumference[edit]

Illustration showing a portion of the globe showing a part of the African continent. The sunbeams shown as two rays hitting the ground at Syene and Alexandria. Angle of sunbeam and the gnomons (vertical pole) is shown at Alexandria, which allowed Eratosthenes' estimates of radius and circumference of Earth.

Eratosthenes calculated the circumference of the Earth without leaving Egypt. He knew that at local noon on the summer solstice in Syene(modern Aswan, Egypt), the Sun was directly overhead. (Syene is at latitude 24°05′ North, near to the Tropic of Cancer, which was 23°42′ North in 100 BC^[16]) He knew this because the shadow of someone looking down a deep well at that time in Syene blocked the reflection of the Sun on the water. He measured the Sun's angle of elevation at noon on the same day in Alexandria. The method of measurement was to make a scale drawing of that right triangle with the vertical rod and its shadow as its legs and to measure the acute angle subtending to the shadow. This turned out to be about 7°, or 1/50th of the way around a circle. Taking the Earth as spherical, and knowing both the distance and direction of Syene, he concluded that the Earth's circumference was fifty times that distance.

Dynamics "Newton's Laws"

UNIT: DYNAMICS

DAY: 29 INTRODUCTION

ACTIVITY:Drawing & Labeling FBD

FUNDAMENTAL SKILLS: 

• Identify and Name Forces

•  FBD CLICK HERE (Complete ALL FBD and PUT IN YOUR NOTEBOOK)

• Sum of F equation (Write The Sum of the Forces and put in your notebook)

KEY IDEAS:

• NEWTON'S LAW'S 

  State:Define:Describe:Differentiate:Give examples 

    Practice Questions

Complete and Put Your Solutions in your NOTEBOOK
IDENTIFY KEY DIFFERENCES in the PROBLEMS
WRITE THE KEY PSS ASSOCIATED WITH EACH

		ILW# 4.1 (Chapter 4 Page 93 Problems 4, 6)
		ILW# 4.2 (Chapter 4 Page 104 Problem 82)
		ILW# 4.3 (Chapter 4 Page 114 Problems 46, 53)
		ILW# 4.4 (Chapter 4 Page 118 Problem 90)

Objectives

After studying the material of this chapter, you should be able to:
1. State Newton's three laws of motion and give examples that illustrate each law.State:Define:Describe:Differentiate:Give examples 
2. Explain what is meant by the term net force.
3. Use the methods of vector algebra to determine the net force acting on an object.
4. Define each of the following terms: mass, inertia, weight and distinguish between mass and weight.
5. Identify the SI units for force, mass, and acceleration.
6. Draw an accurate free body diagram locating each of the forces acting on an object or a system of objects.
7. Use free body diagrams and Newton's laws of motion to solve word problems.