Webopedia on Google+Webopedia on TwitterWebopedia on FacebookTech Bytes Blog
Main » TERM » O »

Ohm's Law

A mathematical equation that shows the relationship between electric voltage, current and resistance. Ohm��s Law was named after Bavarian mathematician and physicist Georg Ohm.

Ohm��s Law can be stated as three mathematical equations, all derived from the same principle. In the following equations, V is voltage measured in volts, I is current measured in amperes and R is resistance measured in ohms:

  • V = I x R
  • R = V / I
  • I = V / R
Knowing any two of the values of a circuit, one can determine the third using Ohm��s Law. For example, if a circuit has a current of 2 amperes, and a resistance of 1 ohm, then according to Ohms Law, voltage equals 2 (V = 2 x 1).

Typically, Ohm��s Law is only applied to DC circuits and not AC circuits.

Note well: The letter "E" is sometimes used in representations of Ohm��s Law for voltage instead of "V."







TECH RESOURCES FROM OUR PARTNERS
DID YOU KNOW?
The Five Generations of Computers

Learn about each of the five generations of computers and major technology developments that have led to the current devices that we use today. Read More »

Small Business Marketing's Greatest Hits

The following compilation of small business marketing tips highlights some of the expert advice published over at Small Business Computing. Read More »

13 Best Free Android Apps

From secure messaging to document editing, our top free must-have apps have been rated, reviewed and named the best free Android apps of 2015. Read More »

QUICK REFERENCE
5 Best Cloud Storage Services

With cost and security in mind, we look at five cloud storage options that will suit the needs of most home and SMB owners. Read More »

Windows 10 Tips for Desktop PC

Five basic tips to help you customize Windows 10 on your desktop PC. Read More »

29 Free Android Apps for Cash-Strapped Students

From wacky alarm clocks to lecture hall tools and after class entertainment, these Android apps are a good fit for a student's life and budget. Read More »