l i n u x - u s e r s - g r o u p - o f - d a v i s
Next Meeting:
July 7: Social gathering
Next Installfest:
Latest News:
Jun. 14: June LUGOD meeting cancelled
Page last updated:
2007 Feb 03 10:21

The following is an archive of a post made to our 'vox-tech mailing list' by one of its subscribers.

Report this post as spam:

(Enter your email address)
Re: [vox-tech] ohms law
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [vox-tech] ohms law

On Fri, 2 Feb 2007, Jimbo wrote:
I am a mechanic by trade. I am good at diagnosing electrical and drivability. I have seen a few times that high resistance in the negative leg of a circuit can take out components like computers, modules and even not-so-complicated devices like bulbs and switches. What I don't understand is why. Ohm's law states that E=IXR. If this is the case then if resistance is high it will decrease amperage. I would tend to think that just the opposite would happen...component would just lose power and not fry.
Dear Jimbo,

You're right that the current should drop if the total resistance increases, since the battery voltage is practically fixed. My thought while I was reading this was that noise in the circuit, from say corrosion at the negative battery connection, could explain the failure of components. Unlike any other type of device I can think of, some electric motors can burn out if they aren't getting enough power because they cool themselves while turning. On the other hand, incandescent light bulbs will last a very long time if run at less than their full operating voltage (such as a 220 volt light bulb run at 110 volts). I would also expect the part of the circuit causing the resistance, such as a frayed cable, to get hot and burn out in that place, since power = EI = RI^2


vox-tech mailing list

LUGOD Group on LinkedIn
Sign up for LUGOD event announcements
Your email address:
LUGOD Group on Facebook
'Like' LUGOD on Facebook:

Hosting provided by:
Sunset Systems
Sunset Systems offers preconfigured Linux systems, remote system administration and custom software development.

LUGOD: Linux Users' Group of Davis
PO Box 2082, Davis, CA 95617
Contact Us

LUGOD is a 501(c)7 non-profit organization
based in Davis, California
and serving the Sacramento area.
"Linux" is a trademark of Linus Torvalds.

Sponsored in part by:
O'Reilly and Associates
For numerous book donations.