FCC Technician Exam Question Of The Day (T5D12)

Q) What is the voltage across a 10-ohm resistor if a current of 2 amperes flows through it?

A) 20 volts

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 = 2 amperes * 10 ohms = 20 volts