Concept explainers
Predict/Calculate A spark plug in a car has electrodes separated by a gap of 0.025 in. To create a spark and ignite the air-fuel mixture in the engine, an electric field of 3.0 × 106 V/m is required in the gap. (a) What potential difference must be applied to the spark plug to initiate a spark? (b) If the separation between electrodes is increased, does the required potential difference increase, decrease, or stay the same? Explain. (c) Find the potential difference for a separation of 0.050 in.
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