11. Electromagnetic waves are sometimes used to disinfect drinking water. Which type of electromagnetic radiation is used in this way?
Answer: D
Ultraviolet radiation is used to disinfect drinking water.
Ultraviolet radiation is effective in killing bacteria and viruses in drinking water, making it a common method for disinfection.
A) Infrared radiation
Infrared radiation is primarily used for heating applications and does not have the necessary energy to effectively kill microorganisms in water. Therefore, it is not suitable for disinfection purposes.
B) Visible light
Visible light is not effective for disinfection as it does not possess enough energy to inactivate pathogens. While sunlight can help in some natural disinfection processes through photochemical reactions, it is not a reliable method compared to ultraviolet radiation.
C) Radio waves
Radio waves are typically used for communication technologies and lack the energy required to kill bacteria and viruses. Consequently, they are not utilized in the disinfection of drinking water.
D) Ultraviolet radiation
Ultraviolet radiation has a wavelength that can effectively disrupt the DNA of microorganisms, rendering them inactive and unable to reproduce. This characteristic makes UV radiation a widely accepted method for disinfecting drinking water.
Conclusion
Ultraviolet radiation is definitively the correct answer as it specifically targets and eliminates pathogens in drinking water, a function that the other options—infrared radiation, visible light, and radio waves—cannot perform effectively. Each of these alternatives lacks the necessary properties to serve as a disinfection method, underscoring the unique role of ultraviolet radiation in water treatment processes.