Here are the reasons why one might (at any age) go to see an ob/gyn or midwife: 1  To get birth control. 2  To have STI testing -- if you're experiencing symptoms, or you've had unprotected sex, you should probably have some STI tests done.
A: Gamma rays are used in many different ways; one of the most common uses is inspecting castings and welds for defects that are not visible to the naked eye. Another common use of gamma rays is in the treatment of certain types of cancer.
Our eyes are detectors which are designed to detect visible light waves (or visible radiation). Visible light is one of the few types of radiation that can penetrate our atmosphere and be detected on the Earth's surface. As we have seen from the section on the discovery of infrared, there are forms of light (or radiation) which we cannot see.