Final answer:
The power dissipated by a resistor is commonly represented by the formula P = I²R, which directly relates the power dissipation to the square of the current through the resistor and its resistance.
Step-by-step explanation:
The power dissipated by a resistor in an electrical circuit can be calculated using several formulas based on Ohm's law. The correct expression for the power dissipated is P = I²R or P = V²/R, where I is the current through the resistor, R is the resistance, and V is the voltage across the resistor. Therefore, the correct answer to the question of what formula best represents the power dissipated by a resistor is option D. IR². It is important to note that this answer is not consistent with the formulas provided and hence could be a misprint. A more common form of the formula for power dissipation in a resistor is P=I²R, which directly relates to the current and resistance.