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Compact fluorescent bulbs (CFLs) are a popular choice for energy efficiency today. Although they have a higher initial cost than traditional incandescent bulbs, they offer significant long-term savings in both energy use and lifespan.

A key feature of CFLs is their efficiency. They use much less electricity to produce the same amount of light. For example, a standard CFL can provide illumination equivalent to a 100-watt incandescent bulb while only using 23 watts of power. This reduced power consumption leads to lower electricity bills.

Furthermore, CFLs last significantly longer than their incandescent counterparts. On average, a CFL can last about 10,000 hours, providing consistent lighting for many years when used regularly. In contrast, incandescent bulbs typically last only around 750 hours. This means, over time, you need to purchase fewer replacement bulbs, further saving money and reducing waste.

Overall, while the upfront cost of CFLs might seem daunting, their longer lifespan and lower energy consumption result in efficient lighting solutions that are both cost-effective and environmentally friendly.

Incandescent bulbs have been a staple lighting choice for many years due to their simplicity and low initial cost. These bulbs work by passing an electric current through a thin filament, heating it until it produces light.

While incandescent bulbs are inexpensive, they are not energy efficient. They typically consume more electricity to produce the same amount of light as their modern counterparts like CFLs. For instance, to achieve the same brightness as a 23-watt CFL, an incandescent bulb requires 100 watts of power.

Another downside to incandescent bulbs is their shorter lifespan. On average, these bulbs last only about 750 hours, meaning you'll need to replace them far more frequently than CFLs. This can contribute to increased costs over time despite the lower upfront price.

However, for those times when budget constraints are tight in the short term, incandescent bulbs may be a go-to option. But for long-term savings and efficiency, alternatives like CFLs offer significant benefits.

Understanding electricity costs is crucial for determining the true expense of operating various light bulbs. This involves not just the cost per bulb but also how much energy they use over time.

Electricity is typically billed by the kilowatt-hour (kWh), which is a measure of energy use. For instance, if electricity costs $0.080 per kWh, switching to energy-efficient lighting like CFLs can significantly reduce your monthly electricity bills.

To calculate total electricity costs for any bulb over a period, you multiply the wattage of the bulb by the total number of hours it's used, then divide by 1,000 to convert to kWh, and finally multiply by the cost per kWh.

For a more concrete example, running a 23-watt CFL for 4 hours per day over 3 years results in a far lower electricity cost compared to a 100-watt incandescent bulb running for the same period. This demonstrates how making informed lighting choices can lead to substantial savings over time.

Calculating resistance is an important part of understanding how electrical devices like light bulbs work. Resistance is a measure of how much a device opposes the flow of electric current, and it's calculated using Ohm's Law.

Ohm's Law states that the power (P) used in an electrical circuit is related to the voltage (V) across the circuit and the resistance (R) of the circuit by the formula: \( P = \frac{V^2}{R} \).

To calculate the resistance of a "100-W" compact fluorescent bulb (which actually uses 23 watts at 120 volts), you rearrange the formula to solve for resistance: \( R = \frac{V^2}{P} \).

Plugging in the values, you find \( R = \frac{120^2}{23} \), which results in approximately 626.087 ohms. Understanding this concept helps to appreciate how efficiently a bulb uses electricity, which is vital for optimizing both cost and performance.