Q:
# How are current and voltage related?

**Voltage, or electrical pressure, in a system produces a proportionate amount of current when placed across electrical resistance.** Ohm's law indicates that 1 volt passed through 1 ohm of resistance produces 1 ampere of current, or electrical flow. Voltage and current, therefore, have a direct relationship most of the time.

Credit:
C.P.Storm
CC-BY-2.0

The lower the electrical resistance of an object, the more easily current can pass through it. The simplest equation is I = V/R, where V is voltage, R is resistance, and I is current. Even relatively low voltages can produce current sufficient to power appliances. Also, there is no such thing as infinite resistance, so even so-called insulators are capable of conducting electricity when exposed to a high enough voltage; lightning is an example of this.

Alternating current muddies the relationship between voltage and current. In an AC circuit, the current constantly alternates direction, hence the name. Typically, an AC circuit includes capacitors and/or inductors, which each bring voltage and current slightly out of sync in their rising and falling phases. In a circuit with an inductor, the voltage leads the current; in a circuit with a capacitor, the current leads the voltage. This keeps a steady flow of power through an electrical appliance.

Learn more about Electricity-
Q:
## Are voltmeters and ammeters both methods of measuring resistance?

A: Neither a voltmeter nor an ammeter measures resistance directly; a voltmeter measures voltage and an ammeter measures amperage or current. However, using O... Full Answer >Filed Under: -
Q:
## What is the equation for voltage?

A: The equation for voltage can be written as the current multiplied by the resistance. Voltage is defined as the electric potential energy at a given point i... Full Answer >Filed Under: -
Q:
## How do you calculate the amperage of copper wire?

A: To calculate the amperage of copper wire, divide the total wattage by the voltage of the system. Wattage is the sum of the electrical power of all devices ... Full Answer >Filed Under: -
Q:
## What is a metal oxide varistor?

A: A metal oxide varistor is a commonly used component that protects heavy electronic devices from voltage surges. It also causes the machine to short circuit... Full Answer >Filed Under: