Turn in 9a

Circular Motion

Curves, Centrifugal, Centripetal Forces Going around a curve smushes you against window Understand this as inertia: your body wants to keep going straight but the car is accelerating towards the center of the curve The Car accelerations  you think you’re being accelerated

Centripetal, Centrifugal Forces, continued The car is accelerated toward the center of the curve by a centripetal (center seeking) force In your reference frame of the car, you experience a “fake”, or fictitious centrifugal “force” Not a real force, just inertia relative to car’s acceleration Centripetal Force on car velocity of car (and the way you’d rather go)

Centripetal Force What provides it?

Car Around a Curve - Friction If there isn’t enough friction (icy or wet road), the car doesn’t make the curve!

Mythbusters!

Our Lab

Lab – How do mass, velocity and radius affect centripetal force? Three investigations Fc versus velocity Mass versus velocity Radius versus velocity Some values are filled in already

Lab Notes Yesterday we discussed calculating tangential velocity. To stop – pull down on string! Space yourselves out. Think ahead. No droopage – no tiltage. Keep strings neat and untangled.