19-09-2015, 06:14 AM
it's always tricky to identify this sort of conceptual problem at a distance but here goes.
Voltages are always measured ACROSS something. You connect the voltmeter to 2 points in the circuit and you are measuring the voltage between them. Sometimes the very descriptive term "potential difference" is used.
Currents flow THROUGH something. To measure a current you have to break the circuit and insert the ammeter.
This diagram http://www.ryerson.ca/~kantorek/Circuitbasic.gif shows an ammeter and voltmeter correctly conencted. In this case the source of power is DC from a battery and the load is a resistance. I found the diagram on this page http://www.ryerson.ca/~kantorek/EES512.html where there's a nice simple explanation of what's happening.
Nick, hope this helps.
Voltages are always measured ACROSS something. You connect the voltmeter to 2 points in the circuit and you are measuring the voltage between them. Sometimes the very descriptive term "potential difference" is used.
Currents flow THROUGH something. To measure a current you have to break the circuit and insert the ammeter.
This diagram http://www.ryerson.ca/~kantorek/Circuitbasic.gif shows an ammeter and voltmeter correctly conencted. In this case the source of power is DC from a battery and the load is a resistance. I found the diagram on this page http://www.ryerson.ca/~kantorek/EES512.html where there's a nice simple explanation of what's happening.
Nick, hope this helps.
www.borinsky.co.uk Jeffrey Borinsky www.becg.tv
