Electricity- Voltage

Current flowing in a circuit is analogous to the flow of water from a higher reservoir to a lower one, as shown in the animation on the right. The pump acts to maintain a pressure difference between the two reservoirs. This pressure difference allows water to flow in the pipe that connects the two reservoirs and do some work in turning the wheel.

Similar to the pump, a battery maintains a suitable electrical pressure difference (potential difference) across the circuit and allows charge to flow resulting in electrical current.

Voltage
Voltage is the measure of the energy given to moving electrons in a circuit. Lets think of it as the push the electrons receive in order to move through the circuit. Now a 6V battery can push a larger current around the circuit than a 1.5V battery.
Current flowing in a circuit is analogous to the flow of water from a higher reservoir to a lower one, as shown in the animation on the right. The pump acts to maintain a pressure difference between the two reservoirs. This pressure difference allows water to flow in the pipe that connects the two reservoirs and do some work in turning the wheel. Similar to the pump, a battery maintains a suitable electrical pressure difference (*potential difference*) across the circuit and allows charge to flow resulting in electrical current.
	High voltage can create some spectacular displays as charge jumps from the wire with high potential to the wire with low potential. Click to see a 120kb movie of the discharge pictured on the right, The Van de Graaff generator is a fine example. When fully charged to a high potential and the earthing rod moved close to the sphere, a large spark results and charge flows through the wire leading to the ground. This flow of charge is not maintained as the sphere and the ground quickly reach a common potential.
Resistance