Light, Color and the Blackbody Curve: Practice Problem Solutions

1. Speed of light c = wavelength x frequency, so a longer wavelength means a lower frequency.

2. Radio, microwave, infrared, visible, ultraviolet, X-ray, gamma ray.

3. 2,898,000 / 6,000 = 483 nm (blue-green; about the same as the Sun).

4. The blue star. A hotter blackbody peaks at a shorter wavelength, which is bluer.

5. It increases by 2 to the 4th = 16 times (Stefan-Boltzmann law).

6. Its light is a mix of all colors in the rainbow, and the mix looks white.

7. T = 2,898,000 / 500 = about 5,800 K.