Multiple choice

Tesla, a high frequency current, is known as the:

  1. red ray

  2. violet-ray

  3. infrared ray

  4. ultraviolet ray

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Tesla high-frequency current is historically referred to as the violet ray due to the color of the gas discharge in the glass electrode. It is not an infrared or ultraviolet ray.