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The Question

(Submitted January 09, 1998)

Hi, I'm in 8th grade and my science class is learning about the the electromagnetic spectrum. My question is why are gamma-rays so much more harmful than radio waves? I already understand that gamma-rays have a higher energy level in them than radio waves, but what makes this energy so harmful?

The Answer

The reason gamma-rays are more harmful then radio waves is because light can be thought of as particles (photons) as well as electromagnetic waves. A radio photon doesn't have much energy and doesn't travel through matter well (that's why you don't pick up radio well in a tunnel). A gamma-ray photon has enough energy to damage atoms in your body and make them radioactive, and gamma-rays can easily penetrate into your body. It's like the difference between getting hit by sand or a bullet. It takes a lot of sand to do any damage, but only one bullet.

Thanks for your question.

Eric Christian
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