connect 2 different wire gauge to pos and neg speaker terminal

I don’t know what the gauge of the leads is, but given that the total length of the two leads is about 8 feet I suspect the lead resistance is a significant contributor to the 0.1 ohms, together with round-off due to the limited resolution.

Regarding fuse resistance, you might find the information on page 2 of this Littelfuse datasheet to be of interest. For the 4 amp 250 volt slow blow 6.3 x 32 mm glass fuse which is among the many listed, the "cold" resistance (meaning the resistance with negligible current being conducted) is indicated as 0.0311 ohms. So for a design which puts say half the rated max current through it the voltage drop would be a bit more than 0.06 volts.

So for a design which puts say half the rated max current through it the voltage drop would be a bit more than 0.06 volts.

herman
1,950 posts                                                                      05-26-2010 10:21pm

Jea, There are positive and negative charges and they are what they are. They do not change from positive to negative. In the case of a wire there are negative charges in motion but in some mediums there are + charges in motion and in some there are both.

So it isn’t + 0 - 0 + 0 - as in the charges are changing polarity it is L 0 R 0 L 0 as in the negative charges are vibrating left and right around a zero point.

If electric current is the movement of charge what is wrong with using the word current in place of the word charge?

Any place you see "current" you can substitute "movement of charge." If you say movement of current you are saying movement of movement of charge. It is redundant.

Look at it this way. In order for something to move it must exist. Current is not a thing or a form of energy, it is a word that describes movement. If water stops flowing the water is still there but there is no current. Did the current just disappear? No, it never existed, it is a concept, not a thing.

With the load consuming power from the supplying alternating voltage source explain the process movement of current to the load.

Thank you, thank you, thank you for asking. That question is a perfect example of why "alternating current flow" is a very bad description of what is going on.

In a nutshell AC current does not move or flow to the load.. That is the very heart of my debate with simply_q.

As stated above current does not move. Current means something is moving. If we switch to charge instead of current then those don’t move to the load either. The charges in an AC circuit merely sit there and vibrate.

Power isn’t moving to the load either. Power is the rate at which we transfer energy. Power is not a thing, it is not energy, it cannot be moved or consumed.

So what’s moving from the source to the load? Energy. A wave of electromagnetic energy moves down the wire and the energy in it is transferred to the load. Charges are vibrating everywhere around the path but energy is flowing in one direction...source to load. It is converted into another form of energy like heat or light, or motion, or it is launched into space if the load is an antenna.

As stated above current does not move. Current means something is moving. If we switch to charge instead of current then those don’t move to the load either. The charges in an AC circuit merely sit there and vibrate.

If you say the AC fuse blew because there was too much current flowing through it everybody nods in agreement even though that isn’t true. If you say the wire in the fuse melted because it got too hot after absorbing energy from the electromagnetic wave people look at you like you are insane and want to argue that vibrating electrons constitute current flow.

These really are confusing topics as we have discovered in this thread. People frequently confuse energy and power. Most people think current is a thing when it is not. It was pounded into our heads that current flow is the same everywhere in a series circuit so we incorrectly think charges are flowing through components in an AC circuit. Yea I know, I sound like a broken record, but you asked/

The problem is there are many technically incorrect phrases that are so ingrained that we can’t seem to get away from them. Everybody says it including me but power can’t really be consumed because it isn’t a thing, it is the rate at which energy flows, but if you say an amplifier consumes 100 watts of power everybody nods in agreement. If you correctly say energy flows into that amp at the rate of 100 Joules per second they look at you like you are nuts.