Using Ohm's law, which formula represents power dissipated by a resistor?

Prepare for the NCEA Level 3 Electricity Exam with flashcards and multiple choice questions. Each question comes with hints and explanations. Get ready for your test!

Multiple Choice

Using Ohm's law, which formula represents power dissipated by a resistor?

Explanation:
The power dissipated by a resistor can be represented using multiple equations derived from Ohm's law, which states that Voltage (V) = Current (I) x Resistance (R). Each of the options provided reflects a correct relationship involving power (P), current (I), voltage (V), and resistance (R). One fundamental formula for power is P = IV, indicating that the electrical power is the product of current flowing through a circuit and the voltage across the resistor. Additionally, by substituting Ohm's law into this equation, you can derive other expressions for power. From P = IV, if you substitute for voltage (V = IR), the equation becomes P = I(IR), which simplifies to P = I²R. This shows how current squared times resistance also gives power. Similarly, you can manipulate the original formula P = IV to derive another relationship. If you substitute for current (I = V/R), the equation becomes P = (V/R)V, which simplifies to P = V²/R. This indicates that voltage squared divided by resistance provides another expression for power. Thus, all three formulas are valid expressions for calculating power in a resistor, reinforcing the idea that multiple relationships exist to define how power, voltage, current

The power dissipated by a resistor can be represented using multiple equations derived from Ohm's law, which states that Voltage (V) = Current (I) x Resistance (R). Each of the options provided reflects a correct relationship involving power (P), current (I), voltage (V), and resistance (R).

One fundamental formula for power is P = IV, indicating that the electrical power is the product of current flowing through a circuit and the voltage across the resistor.

Additionally, by substituting Ohm's law into this equation, you can derive other expressions for power. From P = IV, if you substitute for voltage (V = IR), the equation becomes P = I(IR), which simplifies to P = I²R. This shows how current squared times resistance also gives power.

Similarly, you can manipulate the original formula P = IV to derive another relationship. If you substitute for current (I = V/R), the equation becomes P = (V/R)V, which simplifies to P = V²/R. This indicates that voltage squared divided by resistance provides another expression for power.

Thus, all three formulas are valid expressions for calculating power in a resistor, reinforcing the idea that multiple relationships exist to define how power, voltage, current

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