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Question
Consider the situation shown in the figure. What are the signs of q1 and q2? If the lines are drawn in proportion to the charges, what is the ratio q1/q2?
Solution
The electric lines of force are entering charge q1; so, it is negative. On the other hand, the lines of force are originating from charge q2; so, it is positive. If the lines are drawn in proportion to the charges, then
`q_1/q_2 = 6/18`
`⇒ q_1/q_2 = 1/3`
6 lines are entering q1 and 18 are coming out of q2.
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