🔍 Key Concepts

• Ohm's Law (V = I × R) for finding resistance • Series circuit behavior: same current flows through resistor and filament • Required voltage drop across the resistor when using a 6 V source for a 5 V filament

💭 Think About

• What current does the filament require based on its rating, and will that same current flow through the resistor in series? • How many volts must be dropped across the resistor so that the filament only sees its rated voltage? • Once you know the needed voltage drop and the current, how can you use Ohm's Law to find the resistor value?

✅ Before You Answer

• Confirm the filament current rating (in amperes) and that this is the current through the resistor in a series circuit • Calculate the voltage difference between the battery (6 V) and the filament rating (5 V) to find the voltage across the resistor • Use R = V / I with correct units (volts, amperes, ohms) and compare your result to the closest answer choice