1. Chapter 7
Power

2. Objectives After completing this chapter, you will be able to:
Define power as it relates to electric circuits
State the relationship of current and voltage
Solve for power consumption in an electrical circuit
Determine the total power consumption in a series, parallel, or series-parallel circuit

3. Power Power Watt Rate at which energy is delivered to a circuit
Rate at which energy is dissipated by the resistance in a circuit
Watt
Basic unit of power

4. Power (cont’d.)
Relationship of power, current, and voltage may be expressed as:
P = I x E, where:
I represents current through the circuit
E represents voltage applied to the circuit

5. Power Application (Circuit Analysis)
Total power dissipated in a series or parallel circuit:

6. Summary
Power is the rate at which energy (heat) is dissipated in a circuit
Power is measured in watts
Power is directly proportional to current and voltage
P = IE