FCC Technician Exam Question Of The Day (T5D10)

Q) What is the voltage across a 2-ohm resistor if a current of 0.5 amperes flows through it?

A) 1 volt

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:
E = I * R
E = 0.5 amperes * 2 ohms = 1 volt