Electric Current and Ohms Law Electric Potential EnergyEPE
- Slides: 20
Electric Current and Ohm’s Law
Electric Potential Energy(EPE) • Particles with charges have potential energy. • Opposite charges are attracted to each other. • Like charges are repelled.
Electric Potential Energy (EPE) • When two opposite charges are held apart, electric potential energy is present
Electric Potential Energy (EPE) • When two of the same charges are pushed together, potential energy is present.
Unit of Electric Potential (Voltage) • The unit of electric potential is volts.
What is an electric current? • An electric current is the flow of charged particles. • Particles always move from areas with many charged particles to areas with very few charged particles.
What is an Ampere (A)? • An ampere is the unit of electric current. • Nearly always called an amp • 1 ampere = 1 coulomb of charge every second • 1 ampere = 1 coulomb/second
What causes an electric current? • A difference in energy potential (volts) causes charged particles to flow • The current will continue to flow until the volts are equal.
How can a current continue flowing? • A current can continue to flow as long as the voltage difference remains. • Batteries and generators create a voltage difference that allow current to flow.
Two types of current: • Direct current: • All charge flows in one direction • Alternating current: • Charges reverse direction in a set frequency.
What is resistance? • Resistance is the property of a material that resists the flow of charged particles through it.
What is resistance measured in? • Resistance is measured in ohms. • The symbol Ω (omega) is used for ohms.
What affects resistance? • Conductivity • Better conductors offer less resistance • Temperature • Higher temperatures = higher resistance
What affects resistance? • Thickness of the wire • Thin wires have less resistance • Length of the wire • The longer the wire, the more resistance.
What is Ohm’s Law? • For a circuit of a given resistance, the current and voltage are proportional.
Ohm’s Law formula • Current = voltage ÷ resistance • In units: amperes = volts ÷ ohms
Associated Formulas • Voltage = current x resistance • Resistance = voltage ÷ current
Sample Problem One: • A 4 V battery is attached to a circuit with 2Ω resistance. What is the current? • Current = voltage ÷ resistance • Current = 4 V ÷ 2Ω • Current = 2 A
Sample Problem Two: • A 5 A current is occurring across a 3Ω resistor. What is the voltage? • Voltage = current x resistance • Voltage = 5 A x 3Ω • Voltage = 15 V
Sample Problem Three: • A 20 V source is producing 4 A of current. What is the resistance? • Resistance = voltage ÷ current • Resistance = 20 V ÷ 4 A • Resistance = 5Ω
- Electrical potential energy
- Equipotential lines
- Volts to ev
- Electric potential inside non conducting sphere
- Potential energy of a system of charges
- Joules to newtons
- Energy from electric field
- Electric field from electric potential
- Types of circuits and ohm's law answer key
- A portable electric heater has a resistance of 8 ohms
- Ohm's law
- Point form of ohms law
- Ohms law resistance
- State ohm's law of electricity
- Electric current triangle
- Volts = amps x ohms
- Ohms law emf
- Derive ohms law
- Introduction of ohm's law
- Ohms law worksheet
- A certain light bulb