The formula for finding power in a DC...

Question 1 of 27070csx47vqjHpiAZzGq535n

The formula for finding power in a DC circuit when current and voltage are known:

Back

Question 1 of 27070

Q

The formula for finding power in a DC circuit when current and voltage are known:

🔍 Key Concepts

• Basic DC electrical relationships between power (P), voltage (E or V), current (I), and resistance (R) • Ohm’s Law as it applies to DC circuits • Difference between a formula for power and a formula for power factor

💭 Think About

• Ask yourself: If you know only voltage (E) and current (I), which relationship directly gives you power in watts without needing resistance? • Look at each option and decide: Is this a general power formula, a special case using Ohm’s Law, or something involving power factor that is used more in AC circuits? • Check which choice uses the correct units so that the result comes out in watts when E is in volts and I is in amperes.

✅ Before You Answer

• Verify which expression, when you multiply the units (volts × amperes), gives watts. • Check whether any option that includes R (resistance) is really needed when the question says current and voltage are already known. • Confirm whether power factor (PF) is typically used for AC or DC circuits before choosing any option that includes PF.