FCC Technician Exam Question Of The Day (T5D04)

Q) What is the resistance of a circuit in which a current of 3 amperes flows through a resistor connected to 90 volts?

A) 30 ohms

NJ2X Notes:
Ohm's Law was discovered by Georg Simon Ohm and is worth committing to memory:

E = I * R

or by manipulating the terms algebraically:

I = E / R

or

R = E / I

In this example:

R = E / I
R = 90 volts / 3 amperes = 30 ohms