1. FRICTION, GRAVITY, ELASTIC FORCES
PS CH 10 SEC 2
FRICTION, GRAVITY, ELASTIC FORCES

2. GOAL/PURPOSE PREVIOUSLY YOU LEARNED ABOUT FORCES AND COMBINING FORCES.
NOW, YOU WILL CONTINUE TO COMBINE FORCES AND LEARN HOW GRAVITY AND FRICTION AFFECT MOTION

3. FRICTION
FRICTION- IS A FORCE THAT TWO SURFACES EXERT ON EACH OTHER WHEN THEY RUB AGAINST EACH OTHER.
KEY- THE STRENGTH OF THE FORCE OF FRICTION DEPENDS ON THE TYPES OF SURFACES INVOLVED AND HOW HARD THE SURFACES PUSH TOGETHER.
KEY- FRICTION INCREASES WITH ROUGH SURFACES AND PRESSURE

4. SKETCH

5. TYPES OF FRICTION
STATIC FRICTION- THE FRICTION THAT ACTS ON OBJECT THAT AREN'T MOVING
EX – PUSHING THE DESK ACROSS FLOOR
SLIDING FRICTION- OCCURS WHEN TWO SOLID OBJECTS SLIDE OVER EACH OTHER
EX- BICYCLE BRAKES

7. CONT’D
ROLLING FRICTION- WHEN AN OBJECT ROLLS ACROSS A SURFACE. LESS THAN SLIDING FRICTION
EX- WHEELS, BEARINGS
FLUID FRICTION- OCCURS WHEN A SOLID OBJECT MOVES THROUGH A FLUID. LES THAN SLIDING
EX- MACHINES, SURFING

9. GRAVITY GRAVITY- IS A FORCE THAT PULLS OBJECTS TOWARD EACH OTHER
KEY- ALL OBJECTS EXERT GRAVITY
EX- SOLAR SYSTEM, MOON, EARTH
KEY- THE FORCE OF GRAVITY BETWEEN OBJECTS INCREASES WITH GREATER MASS AND DECREASES WITH GREATER DISTANCE

12. ANSWER THE FOLLOWING P.388 1ABC 2ABC 3AB