A particle of charge 2.0 x 10^-8C experiences an upward force of magnitude 4.0 x10^-6 when it is placed in a particular point in an electric field. a. What is the electric field at that point?
b. If a charge q=1.0 x 10^-8 C is placed there, what is the force on it?

(a) The electric field of the point charge is 200 N/C.

(b) When the charge changes, the force on the charge in the field is 2 x 10⁻⁶ N.

The electric field of the point charge in a given is defined as the force per unit of charge.

When the charge changes, the force on the charge in the field is calculated as follows;

F = Eq

F = (200) x (1 x 10⁻⁸)

F = 2 x 10⁻⁶ N

Learn more about electric force here: link

a) The electric field at that point is newtons per coulomb.

b) The electric force is newtons.

Explanation:

a) Let suppose that electric field is uniform, then the following electric field can be applied:

(1)

Where:

- Electric field, measured in newtons per coulomb.

- Electric force, measured in newtons.

- Electric charge, measured in coulombs.

If we know that and , then the electric field at that point is:

The electric field at that point is newtons per coulomb.

b) If we know that and , then the electric force is:

The electric force is newtons.

when it gains or loses electrons