So Which Is It? Amps Or Volts?
- Thread starter Maser
- Start date
Keep resistance the same and increase voltage, and current rises.
Keep voltage the same level and decrease the resistance, and again - current rises.
Keep voltage the same level and decrease the resistance, and again - current rises.
Sorry, you must be mistaking volts/amps/watts for something else.
If you have a fixed voltage and you lessen resistance, amperage drops.
Please tell me why you think amperage would go up ?
Don't give me someone else's formulae, give me a concrete reason in your own words.
If you can't do that....then...
Tell us why if you decrease the resistance of a speaker (say from 8 ohms to 4 ohms) why is the amplifier able to drive it at nearly double the wattage ?
Yea, I know, confusing, right ?
In shop class we used to hold the spark plug tester and have it shoot out of your finger when you touched someone.
On a related note electricity takes all paths to ground, so when you get zapped by enough miliamps to kick start your heart and it doesn’t.
On a related note electricity takes all paths to ground, so when you get zapped by enough miliamps to kick start your heart and it doesn’t.
They aren't. They're classed as "less than lethal". They can still kill you.
You are wrong.
More resistance= more amps at the same voltage.
Amps = watts ÷ voltage
whatever you're smoking, care to pass it 'round..... because you are wrong.
current (amps, I) = voltage(V) divided by resistance(R)
power (watts, W) = VxI =IxIxR
however, things do get a little different when you go to AC instead of DC because things like inductance and capacitance become reactive. on your amplifier, your speaker is NOT a resistive load, but an inductive load and the ohms rating of the speaker is refering to impedance. the ampifier itself also likeley has lots of reactive components. lowering the impedance of the speaker makes it easier to push more power - BUT, you get the most power in the load when it is impedance matched to the source (this is why the wrong antenna can burn out a transmitter)
Which will cause your electric bill to be higher? A 100 watt light bulb or a 15 watt light bulb? Did the voltage change?
being that your electric bill is based on energy usage - thats watt hours
a 100 watt bulb going for 1.5 hours and a 15 watt bulb going for 10 hours will cost the same.
and grid voltage isnt fixed, it does change through the day and from week to week, here in OZ it can be anywhere from 207V to 253V (measured phase to phase) and still be considered to be in spec - but the frequency is held to a very tight tolerance, they will happily trade voltage stability to keep the frequency in spec.
^^^^^^^^^ The start of the right and wrong discussion
Do you agree with the above statement or not?
if you are asking if I agree with
"
MarshallDodge said:
Keep resistance the same and increase voltage, and current rises.
Keep voltage the same level and decrease the resistance, and again - current rises.
"
then yes Marshall Dodge is exactly correct.
but when you said
"More resistance= more amps at the same voltage. " is wrong.
and I still want to know what in2ishun is smoking and if its been passed round yet ;-)
Put an amp meter on a wire with a 5kw resistance at 240 volts. Now do the same with a 10kw resistance.
You can use a 10 gauge wire for the 5kw resistor. You can not use the same size wire for the 10kw resistor. Why?
WTF is a 10kw resistance kw is kilowatts, a measurement of power NOT a measurement of resistance.
240v into 10KΩ will give you 24 milliamps thats 24 thousandths of an amp which is 5.76Watts
240v into 5KΩ will give you 48 milliamps. 11.52Watts
OTOH
to get 10KW from 240v, you need 41.66A, so 5.76Ω
5KW from 240v, is 20.83A, 11.52Ω
the wire size you need for these currents is highly dependent on length versus acceptable voltage drop - this is because of the wires resistance value per unit length, the wire itself becomes a heater, so electrical insulation heat resistance matters, if the wire is in the open, in a wiring bundle, if there is thermal insulation.....
one of the systems I used to work on had a peak power of 143KW, at 48KV..... it ran through 18guage wire (but only a few inches and was oil cooled) another system I worked on was rated at 90KW/115V and the wires were thicker than my thumb (where the "gauge" system doesnt really work)
I know how many ohms. It was used for a reason. Which you went to where I was going. My next question was going to be... Why do you need a larger wire, path, for the larger resistance?
I was trying to keep it simple and not add in the variables of wire resistance of copper vs aluminum or many other conductive materials.
larger diameter wire make lower resistance
longer wire makes higher resistance.
all else being equal, higher resistance means lower current.
resistance (ohms) is the inverse of conductance (siemens)
keep resistance same and lower voltage, both power (kw) and current (amps, I) reduce
So you need a larger wire for a larger resistor to flow, current, more electricity?
Dang yo, is there a Mil vs MOA debate for everything?
You're both wrong, it's not voltage or amps. Electricity kills you with a knife.
FWIW - All I know is I've never seen a "danger high amps" warning sign on an electrical fence.
You're both wrong, it's not voltage or amps. Electricity kills you with a knife.
FWIW - All I know is I've never seen a "danger high amps" warning sign on an electrical fence.
that doesnt make sense -
more current, yes bigger diameter wire needed.
larger resistance causes lower current.
more electricity?
Read it, learn it, love it.
^^^^This right here.^^^^
I actually had this pic copied, and was about to past it. Then I saw yours.
This thread has given me a headache.
Edit: Oh, and it’s the amps that kill you. If you’ve ever been hit by a spark plug wire, you’ve been hit with 20,000 to 50,000 volts. All it did was make you hurt yourself. It didn’t hurt you because the current was so low. Increase the current, and you get smoke tested.
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I was hoping for the standard the lower the volts the higher the amps. This man may know something about electricity.
I have worked with many electricians who could run some very large and complex projects but could not comprehend this fact.
interestingly enough, and quite counterintuitively, on some devices (like switchmode power supplies, or large electrical mtors on a vfd) lowering the supply voltage can make them dray a higher current (more amps) because by design their output power stays constant.... if output power is constant, input power must also be constant, if P=VI then falling voltage with constant P means increasing current(I)..... but this does not apply to "normal" circuits.
yeah, as for "may know about electricity".... yeah, started as an (aussie) air force avionics technician, went on to do electrical and electronic engineering - so I do know a little.... but I got bored with that and trade transferred across to armament so that I could join EOD - because shooting ,50HEI at unexploded bomb is way more fun than electrical repairs.
This is quite possibly the dumbest post in Bear Pit history. Not only is Ohm's Law the basis for the most elementary analysis of electrical circuits, but it's also easy to prove with a simple equipment and about two minutes.
For everyone's benefit, ignore this man's content.
Somebody here brought a 9volt battery to an amp fight.
Side note, wait until they decide the electric certification tests are racist and drop them.
Side note, wait until they decide the electric certification tests are racist and drop them.
Always had a good laugh seeing a pallet of those in the warehouse.
Question is, did the pallet shrink in size... Or sit in the corner collecting dust.
every electrician I ever met was a whinely lil bitch....fight me... so theres that.
I use to run a v-16 quad turbo Detroit diesel Gen set for a gravel company. We had two of them back to back on a trailer. You could grab both fuel feeds and rev them, it would noticeably twist the trailer. Lol
Everything that came into that warehouse was turned around pretty quickly. Working in a Amazon distribution center was eye opening at how much shit people buy.
I'm going to go with AMPS being more deadly. These are both real killers.
less than lethal = non lethal (at least under recommended use) anything can be lethal when abused. However the point was to allow you to follow the thought process thru to the final destination of the answer to your original question.
Wattage is a different formula. I posted a formula for finding current, not watts.
I said nothing about wattage in my post but you confirmed what I stated. Lowering the resistance of the speaker doubled the current going into the speaker
Here it is in my own words-
Take a fresh 9v battery and put your fingers on the terminals. Feel anything?
Now stick the terminals on your wet tongue. Feel that? That's the difference in resistance.
You need current flow to kill someone. In order to have current flow you need voltage AND resistance. Somewhere around 50 milliamps will kill someone. A 9v battery doesn't have enough potential to do that. Even a 120VAC on dry skin barely has enough potential. Wetting your hands will lower resistance and that's when things get interesting if you are working with electricity.
How Much Current Can The Human Body Withstand?
Of course, more voltage draws more power, but it is not the caliber that kills us but the bullet it shoots. Regardless of the voltage, the real cause of death is the current forced through the body.
www.scienceabc.com
or OP can practice his google and find out in 3.2 seconds
