Electrostatics Electrostatics The branch of science dealing with

Electrostatics

Electrostatics The branch of science dealing with static charges and their electric fields The Greek word for amber, ήλεκτρον electron, was the source of the word 'electricity'

Static Electricity

A little history ä The science of electricity has its roots in observation, known in 600 BC that a piece of amber rubbed with animal fur would attract straw, feathers ä Thales of Miletos (Greece) in credited with this discovery

What is amber? Amber is the fossilized form of tree resin…not the same as sap. Resin is similar to our scabs. It flows out of the tree to plug a hole.

Benjamin Franklin 1752 By tying a key onto a kite string during a storm, Ben Franklin , proved that static electricity and lightning were the same.

The Leyden Jar Progress quickened after the Leyden jar was invented in 1745 The Leyden jar stored electricity and therefore could be studied at length

The Battery A new interest in current began with the invention of the battery. Luigi Galvani had noticed (1786) that a discharge of static electricity made a frog's leg jerk. Galvani thought the leg supplied electricity, but Alessandro Volta thought otherwise. He showed that the metal plate and the Leyden jar were different metals and produced a current. He built the voltaic pile, an early type of battery, as proof.

A quick review of the atom Every atom has a ______ charged ä nucleus surrounded by ____ charged electrons. ä_______ move in and out of fixed pathways around the nucleus positively negatively Electrons

Charges Two kinds: positive and negative (terms coined by Benjamin Franklin) Like charges ____ Unlike charges ______ repel attract

Objects that tend to give up electrons and become positive: Glass Nylon Fur Hair Wool

Be glad you are not a cat http: //www. youtube. com/watch? v=bc. LDx_oi. SMY

Objects that tend to attract electrons and become negative: • Rubber • Styrofoam

Let’s review #1 Balloon on wall

Let’s review #2 Electroscope

Let’s review #3 Water and balloon

Let’s Review #5 2 balloons held near each other

Bill Nye http: //www. youtube. com/watch? v=Z-77 Iza. XGcg