|MLA Citation:||Bloomfield, Louis A. "Question 1052"|
How Everything Works 20 Apr 2018. 20 Apr 2018 <http://howeverythingworks.org/print1.php?QNum=1052>.
Supplying the enormous current needed to maintain the brief arc in the strobe's gas is done with the help of a capacitor, a device that stores separated electric charge. A high voltage power supply pumps positive charge from the capacitor's negative plate to its positive plate, until there is a huge charge imbalance between those two plates. You can often hear a whistling sound as this power supply does its work. The capacitor plates are connected to one another through the gas-filled flashlamp that will eventually produce the light. However, current can't pass through the gas in the flashlamp until some electric charges are injected into the gas. These initial charges are usually produced by a high voltage pulse applied to a wire that wraps around the middle of the flashlamp. When a few charges are inserted into the gas, they accelerate rapidly toward the positive or negative wires that extend from the charged capacitor. As these charges pick up speed, they begin to collide with the gas atoms and they deposit energy in those atoms. Electrons are occasionally knocked out of atoms or out of the wires at the end of the flashlamp and these new charges that enter the gas also begin to accelerate toward the wires. A cascade of collisions quickly leads to a violent arc of charged particles flowing through the flashlamp and colliding with the gas atoms. The flashlamp emits its brilliant burst of light that terminates only when the capacitor's separated electric charges and stored energy are exhausted.