Doppler shift of the light emitted by a race car

Question: What is the percent shift in the wavelength of the light waves emitted by a race car's headlights?

Solution: Looking up the speed of light in the front of the book, v=3.0x10⁸ m/s, we find

i.e. the percentage shift is only 0.000017%.

The second example shows that under ordinary earthbound circumstances, Doppler shifts of light are negligible because ordinary things go so much slower than the speed of light. It's a different story, however, when it comes to stars and galaxies, and this leads us to a story that has profound implications for our understanding of the origin of the universe.