Two kinds of forces Contact forces – you push me Field forces – parachutist gets pulled down by earth

I dream of Jeannie Nugget of gold –How does earth know? Magnet by other magnet –How does magnet know? Charged particle by other –How does charge know?

Big mass, big charge Earth big force on a big mass – elephant Small force on small mass – ant Same with charges

Gravitation field Earth alone has a gravitational field, just ask any dinosaur about the meteor that got captured in it 60,000,000 years ago Earth waits in shadows for a mass to come by Charge has a force field too Waits for another charge to come by NO CONTACT REQUIRED!

Mapping You can map gravitational fields 22,000 miles away: –Earth pulls left –Moon pulls right –Sun right Add them together Repeat at several locations, a map! Electric field mapping is same