Presentation on theme: "Static and Current Electricity April 2006 BY: BRIANNA SHIELDS."— Presentation transcript:
Static and Current Electricity April 2006 BY: BRIANNA SHIELDS
DO NOW 1. What type of wave is a sound wave? 2. Which type of wave from the electromagnetic spectrum has the least amount of energy and the longest wavelength? 3. Why can’t you hear a sound in outer space?
GOAL To differentiate between static and current electricity
Fill in the answers to the video questions while you watch the video.
Proton = P= (+) = nucleus Neutron = N = (0) = nucleus Electron = E = (-) = outside nucleus
Bohr Model of an Atom 8P 8N
More on subatomic particles Neutral atom Forces # P = # E 1. P-E = attract 2. P-P = repel 3. E-E = repel
How do atoms become charged??
Static Electricity 1. The accumulation of extra negative e- on an object 2. Only e- can be transferred 3. Opposite charges attract 4. Like charges repel
Static Electricity Static Electricity Example 5. Extra e- = negatively charged object/atom 6. Missing e- = positively charged object/atom
For each of the following static electricity examples you must do the following: –1. Draw a picture –2. Accompany it with an explanation
Scenario 1: If you shuffle your feet on the carpet, then reach out to touch a metal door knob, you receive a shock by a spark- explain why? Rubbing disturbs the atoms Electrons rubbed off carpet and onto your feet –Shoe has extra e’s (negative chg) –Rug is missing e’s (positive chg) –Extra electrons from the shoe are transferred to the doorknob in the form of an electrical spark
Scenario 2: Clothing sometimes clings together upon removal from the dryer- Why? Electrons rub off clothes and stick to others Some items get a negative charge These clothes are attracted to the ones with a positive charge (clothes missing electrons).
Scenario 3: Charging by Induction- charged object and neutral object attract when atoms in neutral object rearrange their protons and electrons Rub a balloon w/ a cloth to charge it, it accumulates extra negatives on it Bring it close to a wall and it rearranges the atoms on the wall It pulls protons closer and pushing electrons away
Scenario 4: Charged skotch tape Ripping the tape off the desk gives it a charge When the charged rod is brought up to the piece of tape it is either attracted or repelled
Scenario 5: Flying Pepper Charging the rod with fur transfers e’s to the rod Neutral pepper experiences rearrangement of the e’s so the p’s on top are attracted to the pepper
Scenario 6: Bending Water Charge the rod, bring it close to water It rearranges the electrons in the water causing them to be attracted to the negative rod
Scenario 7: Electroscope The negatively charged rod transfers electrons to the metal knob The e’s travel down the metal rod into the aluminum foil Each piece of foil, then has a negative charge- so they repel
Scenario 8: Lightning The accumulation of negative charge in clouds Electrons transfer to positively charged ground to even out the charge Produces electrical spark known as lightning
Conductors & Insulators Conductor Insulator 1. A material that allows e- to move easily through 2. Metals 1. A material that resists e- flow 2. Plastic, wood, rubber, glass
Circuits Current Electricity Creates continuous e- flow
Circuits Parts of a circuit 1. Source –Battery-pumps electrons –Flows from - to + end
Circuits Parts of a circuit 2. Wire –Creates path for e- flow
Circuits Parts of a circuit 3. Load –Resists e- flow, converts it to light or heat –Bulbs, toasters
Circuits Parts of a circuit 4. Switch –Opens and closes circuit path –Open circuit= no e- flow
Examples of simple circuits
Circuit must be closed for electrons to flow……..
Circuits Types of circuit SERIES –Parts connected in a continuous path (one loop) –A break disconnects the whole circuit
Circuits Types of circuit Parallel –Contains various paths for e- flow (branches) –If there’s a break, e- can take a different path
Circuit Drawings 1. Draw a circuit in series with one source, one switch and 4 loads 2. Draw a circuit in parallel with two wire loops, each with a load, one switch and one source
Draw the following circuit examples on your handout: Circuit in series with one source, one switch and 4 loads Circuit in parallel with three wire loops, one source, one switch and three loads (one on each loop).