I 5. An electric field has a strength of 10.0 N/C at a distance of 1.00 m from an unknown charge. At
what distance from the charge does the electric field strength equal 2.50 N/C?

The electric field strength is equal to 2.50 newtons per coulomb at a distance of 2 meters.

Explanation:

From Classic Electrostatic Theory, we find that electric field (), measured in newtons per coulomb, is defined by the following equation:

(1)

Where:

- Electrostatic force, measured in newtons.

- Electric charge, measured in coulombs.

In addition and supposing that phenomena occurs between particles, electrostatic force is modelled after the Coulomb's Law:

(2)

Where:

- Electromagnetic constant, measured in newton-square meters per square coulomb.

, - Electric charges, measured in coulomb.

- Distance between particles, measured in meters.

By applying (2) in (1), we get the following definition of electric field:

(3)

Then, we observe that electric field is inversely proportional to the square of the distance. The following relationship is therefore constructed:

(4)

If we know that , and , then the distance is:

The electric field strength is equal to 2.50 newtons per coulomb at a distance of 2 meters.

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