How to calculate Electric field strength at a point between two charges?

Question by fireablazed: How to calculate Electric field strength at a point between two charges?

If I have two charges of -4nC and -6nC, and they are 40cm apart, what is the electric field strength at the midpoint between these two charges? How do I know if it's positive or negative? Does it matter?

What if the charges are made up of a positive charge and a negative charge? Do I add up the individual field strength?




Best answer:

Answer by astazangasta
Electric field potential is based on what a +1 coulomb charge would experience at that point. Since it's a vector field, you sum up vector charges. So, if you have two positive charges, at the midpoint both vectors will be facing away from each other and they will act in opposition. If you have one positive and one negative, the vectors will act in the same direction - towards the negative charge.

Use Coulomb's law to figure out what the field strength is.

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