PS CH 10 SEC 2PS CH 10 SEC 2

FRICTION, GRAVITY, ELASTIC FRICTION, GRAVITY, ELASTIC FORCESFORCES

GOAL/PURPOSEGOAL/PURPOSE

PREVIOUSLY YOU LEARNED ABOUT PREVIOUSLY YOU LEARNED ABOUT FORCES AND COMBINING FORCES.FORCES AND COMBINING FORCES.

NOW, YOU WILL CONTINUE TO NOW, YOU WILL CONTINUE TO COMBINE FORCES AND LEARN HOW COMBINE FORCES AND LEARN HOW GRAVITY AND FRICTION AFFECT GRAVITY AND FRICTION AFFECT MOTIONMOTION

FRICTIONFRICTION

FRICTIONFRICTION- IS A FORCE THAT TWO - IS A FORCE THAT TWO SURFACES EXERT ON EACH OTHER WHEN SURFACES EXERT ON EACH OTHER WHEN THEY RUB AGAINST EACH OTHER.THEY RUB AGAINST EACH OTHER.

KEYKEY- THE STRENGTH OF THE FORCE OF - THE STRENGTH OF THE FORCE OF FRICTION DEPENDS ON THE TYPES OF FRICTION DEPENDS ON THE TYPES OF SURFACES INVOLVED AND HOW HARD THE SURFACES INVOLVED AND HOW HARD THE SURFACES PUSH TOGETHER.SURFACES PUSH TOGETHER.

KEYKEY- FRICTION INCREASES WITH ROUGH - FRICTION INCREASES WITH ROUGH SURFACES AND PRESSURESURFACES AND PRESSURE

SKETCHSKETCH

TYPES OF FRICTIONTYPES OF FRICTION

STATIC FRICTION-STATIC FRICTION- THE FRICTION THE FRICTION THAT ACTS ON OBJECT THAT AREN'T THAT ACTS ON OBJECT THAT AREN'T MOVINGMOVING

EXEX – PUSHING THE DESK ACROSS – PUSHING THE DESK ACROSS FLOORFLOOR

SLIDING FRICTION-SLIDING FRICTION- OCCURS WHEN OCCURS WHEN TWO SOLID OBJECTS SLIDE OVER TWO SOLID OBJECTS SLIDE OVER EACH OTHEREACH OTHER

EXEX- BICYCLE BRAKES- BICYCLE BRAKES

CONT’DCONT’D

ROLLING FRICTION-ROLLING FRICTION- WHEN AN WHEN AN OBJECT ROLLS ACROSS A SURFACE. OBJECT ROLLS ACROSS A SURFACE. LESS THAN SLIDING FRICTIONLESS THAN SLIDING FRICTION

EXEX- WHEELS, BEARINGS- WHEELS, BEARINGSFLUID FRICTION-FLUID FRICTION- OCCURS WHEN A OCCURS WHEN A

SOLID OBJECT MOVES THROUGH A SOLID OBJECT MOVES THROUGH A FLUID. LES THAN SLIDINGFLUID. LES THAN SLIDING

EXEX- MACHINES, SURFING- MACHINES, SURFING

GRAVITYGRAVITY

GRAVITYGRAVITY- IS A FORCE THAT PULLS - IS A FORCE THAT PULLS OBJECTS TOWARD EACH OTHEROBJECTS TOWARD EACH OTHER

KEY-KEY- ALL OBJECTS EXERT GRAVITY ALL OBJECTS EXERT GRAVITYEXEX- SOLAR SYSTEM, MOON, EARTH- SOLAR SYSTEM, MOON, EARTHKEYKEY- THE FORCE OF GRAVITY - THE FORCE OF GRAVITY

BETWEEN OBJECTS INCREASES WITH BETWEEN OBJECTS INCREASES WITH GREATER MASS AND DECREASES GREATER MASS AND DECREASES WITH GREATER DISTANCEWITH GREATER DISTANCE

ANSWER THE FOLLOWING ANSWER THE FOLLOWING P.388P.388

1ABC2ABC3AB

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