What is Ohm's Law? - Definition from WhatIs.com
Part of the Electronics glossary:

Ohm's Law is the mathematical relationship among electric current, resistance, and voltage. The principle is named after the German scientist Georg Simon Ohm.

In direct-current (DC) circuits, Ohm's Law is simple and linear. Suppose a resistance having a value of R ohms carries a current of I amperes. Then the voltage across the resistor is equal to the product IR. There are two corollaries. If a DC power source providing E volts is placed across a resistance of R ohms, then the current through the resistance is equal to E/R amperes. Also, in a DC circuit, if E volts appear across a component that carries I amperes, then the resistance of that component is equal to E/I ohms.

Mathematically, Ohm's Law for DC circuits can be stated as three equations:

E = IR

I = E/R

R = E/I

When making calculations, compatible units must be used. If the units are other than ohms (for resistance), amperes (for current), and volts for voltage), then unit conversions should be made before calculations are done. For example, kilohms should be converted to ohms, and microamperes should be converted to amperes.

This was last updated in September 2005
Posted by: Margaret Rouse

Related Terms

Definitions

  • wind turbine

    - A wind turbine is a power generating device that is driven by the kinetic energy of the wind. Wind turbines general fall into one of two categories: Horizontal axis wind turbines (HAWTs) and vertic... (WhatIs.com)

  • nanomedicine

    - Nanomedicine is the application of nanotechnology (the engineering of tiny machines) to the prevention and treatment of disease in the human body. (WhatIs.com)

  • planned obsolescence

    - Planned obsolescence is the concept that a product should be designed and produced with the knowledge that it will only be popular, useful and functional for a limited length of time. (WhatIs.com)

Glossaries

  • Electronics

    - Terms related to electronics, including definitions about electrical components and words and phrases about computers, laptops parts, digital cameras, televisions and home appliances.

  • Internet applications

    - This WhatIs.com glossary contains terms related to Internet applications, including definitions about Software as a Service (SaaS) delivery models and words and phrases about web sites, e-commerce ...

Ask a Question About Ohm's LawPowered by ITKnowledgeExchange.com

Get answers from your peers on your most technical challenges

Tech TalkComment

Share
Comments

    Results

    Contribute to the conversation

    All fields are required. Comments will appear at the bottom of the article.