Potential difference and power
8 flashcards to master this topic
Define potential difference across a component in terms of energy transfer.
Potential difference (V) is the energy transferred per unit charge. It is the work done (W) in moving a unit charge (Q) between two points in a circuit. V = W / Q
A 12V battery transfers 600J of energy to a component. Calculate the charge that flows through the component.
Using V = W / Q, rearrange to find Q = W / V. Therefore, Q = 600J / 12V = 50 Coulombs.
What is the relationship between power, potential difference, and current?
Power (P) is the product of potential difference (V) and current (I). P = VI. This equation shows the rate at which electrical energy is converted into other forms of energy.
A resistor has a potential difference of 6V across it and a current of 0.5A flowing through it. Calculate the power dissipated by the resistor.
Using P = VI, power P = 6V * 0.5A = 3 Watts. This represents the rate at which electrical energy is converted into heat in the resistor.
State the equation that relates power, current, and resistance.
Power (P) equals the square of the current (I) multiplied by the resistance (R): P = I²R. This equation is useful when the current and resistance are known.
A 2Ω resistor has a current of 3A flowing through it. Calculate the power dissipated.
Using P = I²R, the power dissipated is P = (3A)² * 2Ω = 18 Watts.
State the equation that relates power, potential difference and resistance.
Power (P) equals the square of the potential difference (V) divided by the resistance (R): P = V²/R. This equation is useful when voltage and resistance are known.
A 10Ω resistor is connected to a 5V power supply. Calculate the power dissipated in the resistor.
Using P = V²/R, the power dissipated is P = (5V)² / 10Ω = 2.5 Watts.
Ready to test yourself?
Practice with MCQ questions to check your understanding of Potential difference and power.
Take QuizStudy Mode
Rate each card Hard, Okay, or Easy after flipping.