Review of last time
1. Newton’s 1st law: Inertia
2. Newton’s 2nd law:
3. Newton’s 3rd law: Paired forces, opposite
directions
4. Forces: Weight and
normal force
Problem-solving strategy for mechanics and
Newton’s 2nd Law
1. Draw a picture
2. Identify all forces acting on the body
3. Draw a free-body diagram
4. Choose a coordinate system
5. Break forces/accelerations down into
components
6. Apply Newton’s 2nd law
Tension
Another “wildcard” force, like normal force
Pull exerted by a rope/string/cable on the object
it’s attached to
Tension tranfers
contact forces
over distances
Springs
Objects that can extend or compress
They exert a force opposing the extension or
compression, and proportional to the amount of
deformation
Springs
The rest of the class will be examples:
Chapter 4, Problem 5
Chapter 4, Problem 13
Chapter 4, Examples 8-10
You are responsible for understanding these
examples, even if we don’t get to them in class!