A diode allows current to pass easily in one direction and blocks current in the other direction. Diodes are commonly used for rectification which is the conversion of alternating current (AC) into direct current (DC). Because a diode only allows current flow in one direction, it will pass either the upper or lower half of AC waves (half-wave rectification) creating pulsating DC. Multiple diodes can be connected together to utilize both halves of the AC signal in full-wave rectification.

All electricity is the movement of electrons which are subatomic particles that orbit the nucleus of an atom. Electrons occupy various energy levels called shells and how well an element enables the flow of electrons depends on how many electrons occupy its outer (valence) electron shell.

A photovoltaic cell (also known as a solar cell) converts energy from the sun into electrical energy.

Connecting the 10 batteries in series multiplies their voltage while keeping their current the same yielding a 120V 10A configuration. Connecting the 10 batteries in parallel multiplies their current while keeping their voltage the same yieleding a 12V 100A configuration. Using a series-parallel connection, 5 batteries can be connected in series and 5 can be connected in parallel resulting in a 60V 50A configuration.

Resistance is opposition to the flow of current. As resistance increases, current decreases as resistance and current are inversely proportional.