Question

why is test charge just positive and not negative?​

Answer 1

Explanation:

We take positive charge as a test charge because positive charge is higher potential and negative charge is lower potential. Therefore, influence of positive charge on other charges is greater than negative charges. We can also take negative charge but the effect will be lower.

Test charge is kept normally positive because as we all know that the flow of current or major charge carrier are electrons which are negatively charged. So to know what is the forces acting on the test charge due to parameters like current,magnetic field etc, we generally place a test charge or positive polarity.

hope it works out.

Answer 2

Answer:

It is kept normally positive as we all know that the flow of current or major charge carrier are electrons which are negatively charged. So to know what is the forces acting on the test charge due to parameters like current,magnetic field etc. We generally place a test charge.

Explanation:

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