Please explain volts, ohms, etc. 5

[ZAP]

Wish I still had my old physics text book.

 

[roliver]

Since the question asked is brief, I offer this; Voltage is the amount of stored electrical energy (potential) provided by an energy source and its units are given in Volts. Current is a unit of measure of an amount of energy charges passing through a given area for a specific time interval (Coulombs per second or Amperes). Resistance is the amount of work or energy used that impedes the current flow and usually expresses the loss of potential energy or drop through a passive linear device. Through Ohm's law we define this relationship with E (volts) = I (current) * R (ohms). This is simplistic, and basically refers to Direct Current (DC) Circuits, but I hope it helps.

 

[Dan76]

To put it in "Mechanical" terms,
Voltage=Pressure (Measured in Volts)
Current=Flow Rate (Measured in Amps)
Resistance=Resistance (Measured in Ohms)
Power=Power (Measured in Watts)
Assuming simple DC:
1Amp x 1Volt = 1Watt (P=IE)POWER is as easy as PIE
1Amp= 1Volt x 1Volt (E=IR)
All simple problems can be solved by these 2 Equations

Resistance in series is Additive R1+R2+R3...=Rtotal
Resistance in parallell is solved by
1/Rtotal=1/((1/R1)+(1/R2)+(1/R3)+...)
Therefore the sum of parallell resistances must be less than the lowest resistance

DC is Direct Current (Your car battery)
AC is Alternating Current (Your House)
Frequency (Measured in Hertz) is the cycles per second of AC Power, typically 60Hz in the US and 50Hz in Europe (Although some special applications like aircraft use 400Hz)

Some other notes, typical household voltages are 110-120 Volts AC (US) with 220-240 Volts AC being used for large appliances, 220-240 Volts is widely used in Europe
Most cars use 12V DC but older cars may use 6V Dc
A typical battery (AA,C,D) cell in the US is 1.5 Volts

Most US Houses have a 200 Amp Service

And finally 3 KiloWatts=4 HorsePower (Roughly, it's a thumb rule NOT an EXACT conversion)

Hope that Helps a Little

 

[subtech]

A star for Dan76 and for roliver for being patient, practical, and informative!
Unfortunately, there are some "engineers" who frequent these forums who would have responded to this question in a very ugly fashion. I'm very glad to see that did not happen here.
Congrats and thanks to those patient few who are willing to discuss the basics and help those who ask for help.

 

[jraef]

Yes, thats nice and I applaud you as well for having the patience, but read the site description and rules. This is a site for working engineers to help each other, not for non-engineers to get basic engineering advice. That same information was available at Wikipedia, but out of respect for the effort put out by Dan76 and roliver, I for one am not going to red flag it. Don't be surprised if someone else does however.

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