Washington Esthetician State Board Practice Exam

What type of electric flow is primarily featured in a flashlight?

1. High-frequency current

2. Direct current

3. Alternating current

4. Variable current

The correct answer is: Direct current

The type of electric flow primarily featured in a flashlight is direct current. Direct current (DC) consists of an electric charge that flows in one direction only, which is ideal for devices like flashlights that require a steady and continuous source of power. Flashlights typically use batteries that provide direct current. The DC flow ensures that the bulbs or LEDs inside the flashlight operate consistently and effectively without flickering, which would be less practical in a portable and battery-operated device. In comparison, high-frequency current is used in applications such as radio and communication devices, alternating current is generally used for residential and commercial power supplies due to its ability to be transformed easily to different voltages, and variable current refers to an adjustable flow which is not a feature of standard flashlights.