Download Current Electricity

Current Electricity
Electric Current
• is a measure of the number of electrons
that move through a circuit
• the symbol for electric current is (I)
• the unit to measure electric current is the
ampere, the symbol for the ampere is (A)
• the instrument that is used to measure the
electric current in a circuit is called an
ammeter.
Electric Potential
• is a measure of the amount of energy the
electrons possess
• the symbol for electric potential is (V)
• the unit to measure electric potential is
the volt, the symbol for the volt is (V)
• the instrument that is used to measure the
electric potential in a circuit is called a
voltmeter
Electrical Resistance
• an object in an electrical circuit that
impedes the flow of electrons by using
their electrical energy.
• the symbol for electrical resistance is (R)
• the unit to measure electrical resistance is
called the ohm ().
Ohm’s Law
• The voltage drop between two points on a
conductor is proportional to the electric current
flowing through a conductor
• The equation for this relationship is:
•
V=IxR
•
Where:
•
V represents the voltage (measured in volts)
•
I represents the current (measured in amps)
•
R represents the resistance (measured in
ohms)
Ohm’s Triangle
•
•
•
•
I (Current) Amp (a)
R (Resistance) (Ω)
V (Potential Difference)
Volt (v)
5 Step Approach to Solving
Problems
• Step 1: write down the information
given in the questions
• Step 2: write down the required item
• Step 3: write down the equation
• Step 4: substitute the known values
into the equation and calculate the
answer
• Step 5: write a sentence with the
answer
Example: Calculate the amount of current (I) in a
circuit, given values of voltage (V) and resistance (R):