Acharge q produces an electric field of strength 4e at a distance of d away. determine the electric field strength at a distance of d away.

a.) e

b.) e

c.) 36e

d.) 9e

c.) 36E

Explanation:

The magnitude of the electric field is given by the expression

(1)

where k is the Coulomb's constant, q is the charge that generates the field, and d is the distance from the charge.

In this problem, we have that the magnitude of the field at a distance d is 4E, so we can rewrite the previous equation as

Now we want to determine the electric field at a distance of away. Substituting into (1), we find

(2)

We also know that

(3)

So combining (2) with (3), we find a relationship between the original field and the new field:

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