The strength of an electric field depends on the
c. amount of charge on a test charge placed in the field.
a. distance from the charge.
b. amount of charge that produced the field.
d. both a and b

The correct answer is " amount of charge on a test charge placed in the field."

Explanation:

The expression of the electric field at a distance from the source charge is as follows;

Here, q is the charge, E is the electric field, k is constant and r is the distance from the charge.

The electric field and the distance have an inverse relation. It varies inversely as the square of the distance. The electric field is directly proportional to the charge.

The strength of the electric field increases with decrease in the distance from the charge. From the given options, the options (a) and (b) are correct. The electric field depends on the distance from the charge and the amount of charge that produces the electric field.

Therefore, the correct option is (d).

grav forces affect all objects magnetic forces affect magnetic objects and electric currents

it has to be b, about 97 percent.