The electromagnetic spectrum. Electromagnetic waves, which include light, consist of vibrations of electric and magnetic fields, and they all travel at the speed of light. (a) FM radio. Find the wave- length of an FM radio station signal broadcasting at a frequency of 104.5 MHz. (b) X rays. X rays have a wavelength of about 0.10 nm. What is their frequency? (c) The Big Bang. Microwaves with a wavelength of 1.1 mm, left over from soon after the Big Bang, have been detected. What is their frequency? (d) Sunburn. Sunburn (and skin cancer) is caused by ultraviolet light waves having a frequency of around 1016 Hz. What is their wavelength? (e) SETI. It has been suggested that extraterrestrial civilizations (if they exist) might try to communicate by using electromagnetic waves having the same frequency as that given off by the spin flip of the electron in hy- drogen, which is 1.43 GHz. To what wavelength should we tune our telescopes in order to search for such signals? (f) Microwave ovens. Microwave ovens cook food with electromagnetic waves of frequency around 2.45 GHz. What wavelength do these waves have?

The electromagnetic spectrum. Electromagnetic waves, which include light, consist of vibrations of electric and magnetic fields, and they all travel at the speed of light. (a) FM radio. Find the wave- length of an FM radio station signal broadcasting at a frequency of 104.5 MHz. (b) X rays. X rays have a wavelength of about 0.10 nm. What is their frequency? (c) The Big Bang. Microwaves with a wavelength of 1.1 mm, left over from soon after the Big Bang, have been detected. What is their frequency? (d) Sunburn. Sunburn (and skin cancer) is caused by ultraviolet light waves having a frequency of around 1016 Hz. What is their wavelength? (e) SETI. It has been suggested that extraterrestrial civilizations (if they exist) might try to communicate by using electromagnetic waves having the same frequency as that given off by the spin flip of the electron in hy- drogen, which is 1.43 GHz. To what wavelength should we tune our telescopes in order to search for such signals? (f) Microwave ovens. Microwave ovens cook food with electromagnetic waves of frequency around 2.45 GHz. What wavelength do these waves have?