(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The gap in the spark plug of the car is 0.1 cm. What potential difference is needed to produce a spark given that the breakdown strength of air is 3X10^6 V/m.

2. Relevant equations

3. The attempt at a solution

I'm sort of confused by what they're asking...like i tried using the formula V= -Ed but then apparently in the answers, it says 'for 1 m, voltage difference is 3X10^6 V. For 0.1 cm, voltage difference is 0.001 X (3X10^6)= 3000V.

I don't understand why do we need to compare it to 1 m and why when they calculated it, they didn't place a negative sign like in the formula...

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# Homework Help: Electric Potential

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