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Question
A point charge Q is placed at point O as shown in the figure. The potential difference VA – VB positive. Is the charge Q negative or positive?
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Solution
According to the question, VA – VB is positive, which leads to the conclusion that VA > VB , since potential inversely proportional to distance from the charge (\[V \propto \frac{1}{r}\]). Thus, charge at O is positive.
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