Question

The electric field strength E is measured as:

force per unit mass
charge per unit force
force times mass
force per unit charge

Answer 1

The correct answer is
force per unit charge.

In fact, the electric field strength is defined as the electric force per unit charge experienced by a positive test charge located in the electric field. In formula:
$E= \frac{F}{q}$
where
E is the electric field strength
F is the electric force experienced by the charge
q is the positive test charge.