Published on January 7, 2010
Which particles move freely through metals?
Atoms c. Protons
Electrons d. Molecules
What is the charge on the following particles:
8-2 Current Electricity Describe electric current. Identify the two types of current. Explain how voltage produces electric current. Calculate voltage, current, and resistance using Ohm’s Law
Electric Current A steady flow of electrons through a conductor. Measured in amperes or amps (A). Variable is “I”
Direct Current (DC) Charge flows in one direction. battery operated devices Electrons flow from the negative to the positive. Opposite to direction of the current.
Alternating Current (AC) A flow of electrical charge that regularly reverses the flow of charge. American electricity changes directions 60 times a second. Household current is alternating current.
Potential Difference Also known as Voltage. The “push” that causes electrons to flow through a circuit. Measured in volts (V). Variable is “V”
Resistance Anything that slows the flow of electrons through a conductor. Measured in ohms (W ). Variable is “R”
Ohm’s Law The mathematical equation that shows the relationship between current, potential difference and resistance. V = IR Where: I = current in amps (A) V = potential difference in volts (V) R = resistance in ohms (W)
Sample Problem How many 1.5V batteries would be needed to supply 0.83A of current if the appliance offers 5.4W of resistance? I = 0.83A R = 5.4W V = IR V = 0.83A(5.4W) V = 4.482V 4.482V / 1.5V per battery = 2.988 or 3 batteries
Sample Problem If a lamp bulb requires 5.5amps of current supplied at 110volts, how much resistance does it offer? I = 5.5amps V = 110volts R = V / I R = 110V / 5.5a R = 20W
Sample Problem If an electrical appliance offers 24W of resistance, and is connected to a 9.0V battery, how much current will flow? R = 24W V = 9.0V I = V / R I = 9.0V / 24W I = 0.375a
Conclusion What is the relationship between current, voltage, and resistance?
Characteristics of Electricity - Section 8.2 Quiz. ... What unit is used to measured electric current? ? Amperes ? Volts ? Newtons ? Ohms Which ...
Current electricity is the flow of charged particles in a complete circuit.The unit for measuring electric current is the ampere (A), which is defined as ...
1. Warm-up Which particles move freely through metals? Atoms c. Protons Electrons d. Molecules What is the charge on the following particles: Proton-
116 MHR • Section 8.2 Electric Current © 2007 McGraw-Hill Ryerson Limited Name Date Section 8.2 Electric Current Summary Textbook pages 280–289 Before ...
Study online flashcards and notes for 8.2 Electric Current including amperes: unit for measuring electric current; very small currents are measured in ...
8.2 Electric Current Name: Date: Block: (Reference: BC Science 9 pp. 280 - 289) Electric Circuits electric circuit: ...
Vocabulary words for 8.2 Electric Current. Includes studying games and tools such as flashcards.
8.2 Electric CurrentName: Date: Block: ... the electron’s electric potential energy is transformed into another form(s) ... CURRENT ELECTRICITY AND ...
Section 8.2 Electric Current Before You Read 1. Words to Know ... E. the unit of electric current ____ electric load F. the amount of charge passing a