Electric Charge Spectra of Science Amole 2015

All matter is made of atoms Atoms contain: ◦ Protons- Positive ◦ Electrons- Negative ◦ Neutrons- Neutral/ No charge An unequal amount of (+) and (-) makes a material “charged” Electric Charge is measured in coulombs (C) What causes electric charge? + - 0

Objects with opposite charges (one negative, one positive) will attract each other. Objects with like charges (both negative or both positive) will repel each other. What is electric force?

Charge ◦ More charge = greater force Distance ◦ Greater distance = weaker force Does not require contact due to their electric field What affects electric force? + -

(+) and (0) are relatively fixed in the nucleus, but (-) in the outer parts of atom can be transferred between objects. If the nucleus were a size of a marble, the whole atom is the size of a football stadium How do objects become charged?

Charging by friction ◦ rubbing or sliding Charging by contact ◦ touching Induced charge ◦ Charge brought near object How do objects become charged?

Charge Demos -Magnets-Electric force; Distance & charge -Magic wand-friction -2 balloons -Balloon & wall-induced -Door knob-contact -Plasma ball-Electric field

Current and Circuits Spectra of Science Amole 2015

A set of electrical components that supply one or more paths for movement of charges Open- incomplete/broken path Closed- complete/continuous path What is a circuit?

Current: The rate that electric charges move through a conductor Resistance: opposition posed to a circuit (slows down current) What is current and resistance?

Electrical potential energy- energy charges have due to position in the electric field Affected by distance and type of force Measured in joules (J) What causes current? Low PEHigh PE

Forces can be used to push charges in the opposite direction on the electric force to create… Potential Difference –change in electrical PE Measured in volts Often referred to as voltage Batteries can supply this What causes current?

Series- same loop ◦ All resistors on same loop experience same amount of current Parallel- multiple loops ◦ current splits up among the loops with the individual loop currents adding to the total current What is a series and parallel circuit?

One path All resistors on same loop Experience same current through all devices Resistance may differ Voltage can be different What is a series circuit? V = IR R = V/I

Multiple paths All resistors on own loop Same voltage Can have different currents through each device Individual loop currents add up to create the total current Resistance may differ What is a parallel circuit? V = IR R = V/I

A way to draw circuits using symbols What are schematic diagrams?

A way to draw circuits using symbols What are schematic diagrams? Series Parallel

Use students to create circuits: -open -closed -series -parallel Circuit Activity

Current ◦ measure amperes (A) ◦ use ammeter Voltage- ◦ measure volts (V)- ◦ use voltmeter Resistance ◦ measure Ohms (Ω) ◦ Use ohmmeter (on multimeter) ◦ use ohm’s Law equation: V = IR How do I measure A, V, Ω?

A multimeter will measure all values by simply selecting on the dial How do I measure A, V, Ω?

Conductor – a material in which charges move freely and can carry electric current Low resistance Insulator - a material in which charges cannot move freely and does not easily carry electric current High resistance What are conductors and insulators?

Build simple series circuit Test: - paperclip - penny - nickel - foil - index card - wood stick - string - plastic stick Conductors and Insulators