Question

Electromagnetic waves used for purification of water are ______.

Options

• X-rays

• Ultraviolet rays

• Infrared rays

• Ultrasonic rays

Answer 1

Electromagnetic waves used for purification of water are ultraviolet rays.

Explanation:

Ultraviolet (UV) rays, particularly in the UV-C spectrum (wavelengths approximately 254 nm), are employed for water purification. These rays possess germicidal properties; they enter the cells of microorganisms such as bacteria, viruses, and parasites, therefore eliminating their DNA. This inhibits pathogen reproduction and disease symptoms, effectively disinfecting the water without introducing chemicals or altering its taste.