Question

Calculate the magnitude of electric field produced 2.0m away from a 1 nC point charge. Please show your work.

Answer 1

Answer:-

Before solving the problem, we need to know some informations about electric force and electric field.

1) We know that electric field is a region around a charged body in which it's force of interaction can be experienced.

2) The electrostatic force between two charges and seperated by a distance is given by the Coulomb's law,

Where is the unit vector along the direction of force and   is the permittivity of the free space.

3) The intensity of the electric field at any point is equal to the force experienced per unit test charge placed at that point.

i.e.

Where Charge of = 1C

4) The direction of electric field intensity is always away from the charge if charge is positive and towards the charge if charge is negative.

Now consider the problem. By analysing the problem, we can draw a figure as shown below,

Let a unit charge Q₀ placed at the point P. Then according to Coulomb's law, the electro static force experienced by the test charge is,

Then electric field at P is,

Given that q= and .

Also we know that the value of   is

Substituting we get,

Given charge is positive, therefore direction of electric field is away from the charge.

Hence, the magnitude of electric field due to the charge 1nC at a distance 2 m is 2.25 N/C and is directed away from the charge