What is Radiation?

Radiation : Definition

• Radiation is the transfer of energy through waves (electromagnetic radiation) or fast traveling particles (particulate radiation).
• Radiation can be in the form of heat, sound and light.
• Radiation can be felt or seen like light or detected through special instruments like X-ray.
• Radiation from a hot object is shorter and more intense than radiation from a cooler object.
• The Sun, Earth, soil, microwave, television, cell phones all expose us to radiation.

Electromagnetic radiation involves photons (energy that is always moving) traveling in waves (radio which brings sound to our ears) or like particles ( x-rays ). There are two types of radiation within electromagnetic radiation.

• Ionizing radiation has sufficient energy to break atoms to create ions. Eg: electric power.
• Non ionizing radiation causes atoms to move in the molecule only. Eg: microwave heating the food.

Types of Radiation

• Alpha radiation emits out positively charged alpha particles because there are too many protons in the nucleus. Eg: Radium
• Beta radiation emits out negatively charged beta particles because there are too many neutrons in the nucleus. Eg: Hydrogen
• Gamma and X- Ray radiation emit excessive energy from the nucleus. Eg: Iodine

Radiation Therapy for Cancer

Cancer cells start multiplying and destroy your body’s valuable cells one by one. Radiation therapy involves high energy gamma rays killing the cancer cells. External radiation therapy uses a large machine that points at the particular place being affected and emits out radiation rays. In internal radiation therapy, a radioactive substance is injected in the body to kill the tumor cells.

2 Interesting Facts about Radiation

1. Too much exposure to radiation causes cancer as radiation changes cell structures in our bodies.
2. Radiation is measured in curies.

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