Final answer:
The 7 main categories of electromagnetic energy, ranked from lowest energy to highest, are radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays.
Step-by-step explanation:
The 7 main categories of electromagnetic energy, ranked from lowest energy to highest, are:
- Radio waves: These have the longest wavelengths and lowest energies. They are used in communication systems such as radios and cellphones.
- Microwaves: These have shorter wavelengths and higher energies than radio waves. They are used in microwave ovens and Wi-Fi technology.
- Infrared: This category includes heat radiation. It has shorter wavelengths and higher energies than microwaves. It is used in remote controls and thermal imaging.
- Visible light: This is the range of electromagnetic energy that humans can see. It includes the colors of the rainbow.
- Ultraviolet: This category includes rays from the sun that can cause sunburn and skin damage.
- X-rays: These have shorter wavelengths and higher energies than ultraviolet rays. They are used in medical imaging.
- Gamma rays: These have the shortest wavelengths and highest energies. They are produced by nuclear reactions and used in cancer treatment.