I have a resistor with a voltage across it and and a current through it that satisfy the passive sign convention.
the problem wants me to write three different ways in which the power dissapated by the resistor can be calculcated.
i know Ohms law v=ir
and watts law p=iv but i dnt understand what to do next
P=VI
P=I^2R
P=V^2/R
I^2 R
VI
V^2/R
To calculate the power dissipated by a resistor, there are three different ways that you can approach it.
1. Using Ohm's Law:
Ohm's Law states that the voltage across a resistor (V) is directly proportional to the current flowing through it (I), i.e., V = IR. Here, the power dissipated by the resistor (P) can be calculated by using the formula P = VI. Since we have V = IR, we can substitute it into the power formula to get P = I(IR) = I^2R.
2. Using Watt's Law:
Watt's Law states that the power (P) is equal to the product of current (I) and voltage (V), i.e., P = IV. Since you already know the resistor's voltage (V) and current (I), you can directly substitute them to get the power dissipated as P = IV.
3. Using the power formula P = (V^2) / R:
Another way to calculate the power dissipated by the resistor is by using the formula P = (V^2) / R. Here, you square the voltage across the resistor (V) and divide it by the resistance (R) to obtain the power (P).
Remember, in all three methods, the resistor's voltage and current must satisfy the passive sign convention, i.e., the current flows into the positive terminal of the resistor and the positive voltage is across the positive terminal of the resistor.
These three different methods provide you with multiple ways to calculate the power dissipated by a resistor, allowing for cross-verification of results and increased understanding of the concepts involved.