SUMMARY
The resistance of a "90-watt" light bulb connected to an rms voltage of 120V is calculated using the formula R = V²/P. Substituting the values, R = 120²/90, which results in a resistance of 160Ω. An initial incorrect calculation of 0.00625Ω was identified as an algebra error. The correct approach confirms that the light bulb's resistance is 160Ω, providing a clear understanding of the relationship between power, voltage, and resistance.
PREREQUISITES
- Understanding of Ohm's Law
- Familiarity with electrical power calculations
- Knowledge of root mean square (rms) voltage
- Basic algebra skills for manipulating equations
NEXT STEPS
- Study the derivation of Ohm's Law and its applications
- Explore electrical power formulas in AC circuits
- Learn about the significance of rms voltage in electrical engineering
- Practice solving for resistance using various power and voltage values
USEFUL FOR
Students in electrical engineering, physics enthusiasts, and anyone interested in understanding the principles of electrical resistance and power calculations.