PPT Slide
Except for weight, and the observation that
“things tend to fall towards the earth”,
most of our personal experience
with forces comes from contact forces
Contact force examples: hand on table, seat on you,
ground on tires, rope on mass (tension), etc.
Contact Forces act only when two objects are in contact
Your own experience of your weight right now comes from
the seat pushing up on you with a force equal
in magnitude to the earth pulling down.