What is the formula for electrical power when expressed in terms of voltage and resistance?

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Multiple Choice

What is the formula for electrical power when expressed in terms of voltage and resistance?

Explanation:
Power is the rate at which electrical energy is converted or dissipated. The basic relation is P = V × I. To express power with voltage and resistance, substitute I with V / R from Ohm’s law. This gives P = V × (V / R) = V^2 / R. So the formula for power in terms of voltage and resistance is P = V^2 / R. This shows that, at a fixed voltage, increasing the resistance lowers power, while at a fixed resistance, increasing the voltage raises power proportional to the square of the voltage. The other forms, like P = V I or P = I^2 R, are valid but involve different quantities; R / V wouldn’t yield power in watts.

Power is the rate at which electrical energy is converted or dissipated. The basic relation is P = V × I. To express power with voltage and resistance, substitute I with V / R from Ohm’s law. This gives P = V × (V / R) = V^2 / R. So the formula for power in terms of voltage and resistance is P = V^2 / R. This shows that, at a fixed voltage, increasing the resistance lowers power, while at a fixed resistance, increasing the voltage raises power proportional to the square of the voltage. The other forms, like P = V I or P = I^2 R, are valid but involve different quantities; R / V wouldn’t yield power in watts.

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