You size wire by the current. Various insulations are rated for voltage, temperature and the medium where the wire will be run.
Depends on the amperage of the Jacuzzi and if it is 120 or 240 volts.
You can't. A 220 volt dryer requires 220 volts in order to operate properly. It will not run on 110 volts.
Wire is rated in ampacity, You can use only 80% of the rated ampacity. Voltage and amperage are inversely proportional. So at 120 volts alternating current you safely run 1800 watts ( I have added a small safety margin). At 240 volts you can run 3600 watts. I hope this has answered you question Ampsxvolts=watts watts/volts=amps
Depends on what it is powering. The longer the run the more voltage drop you get. For example if you run 200 feet of copper 10 wire you'll lose about 4 volts. There are voltage calculators you can use. The less volts you have the more amps the wire will have. Watts/volts=amps. 10 wire is rated for 30 amps. Do the calculation. You should not go past 80% of 30 amps (24 amps).
If your light bulb voltage rating is under 300 volts then yes it can use 300 volt wire. The voltage rating of the wire is the maximum voltage that the wire can safely carry. The three common insulation groups is 300 volts, 600 volts and 1000 volts.
You size wire by the current. Various insulations are rated for voltage, temperature and the medium where the wire will be run.
Depends on the amperage of the Jacuzzi and if it is 120 or 240 volts.
If you mean too small a wire it depends on the length of the run. Wire has resistance and you will loose voltage. If the run is too long for the wire size then you may end up with far less than the voltage requirement of the electrical equipment used in the out building. You may start with 240 volts and end up with 200 volts. Same thing applies to 120 volts. Measure the voltage at the outlet to see what you have.
South America, Africa and Asia
2 volts, 5 volts, 12 volts. New computers need even less voltage.
You can't. A 220 volt dryer requires 220 volts in order to operate properly. It will not run on 110 volts.
Have you made sure your battery is at 12 volts and not 11 volts? Secondly, 11 volts is more than enough to make the pump run (and start the truck). Low voltage is normally the sign of a bad relay (or wire connector).
about 2.5 volts
Unlikely- European countries run on 240 volts which is about double the US standard.
Wire is rated in ampacity, You can use only 80% of the rated ampacity. Voltage and amperage are inversely proportional. So at 120 volts alternating current you safely run 1800 watts ( I have added a small safety margin). At 240 volts you can run 3600 watts. I hope this has answered you question Ampsxvolts=watts watts/volts=amps
There should be a single wire with a green connector on the end located by the master cylinder. put 12 volts to that wire and the fuel pump should run