Question

You are just going to explain the Doppler shift and Cosmic Background Radiation-what they are and why they're important to how our earth was created.

Also, explain how they provide evidence to how our universe expanded.

Answer 1

i really need the help.. :/

Answer 2

When you see a cop by the roadside writing somebody a speeding ticket, or hear the clamor of a fire truck going by, you're probably not sparing much thought for the expansion of the universe, or even the rotation of the Galaxy. But in fact, all these things are connected. The policeman using his or her radar or laser speed gun to enforce a traffic law is using the same physical principle that scientists use to study the rotation and motion of stars, the distance to the edge of the Milky Way galaxy, and even learn important things about our entire universe. This physical principle is called the DOPPLER SHIFT.

Answer 3

When the fire truck passes, the sound of its siren changes. The sound waves emitted by the approaching fire truck are pushed closer together by its motion, so the notes seem to have a higher frequency than they'd have if you and the fire truck were both parked. In the same way, the sound waves from a receding fire truck are appear to have a lower frequency. The cop waiting by the roadside with his speed gun uses the same physical effect; he bounces a radar wave off your car and measures the frequency of the reflected wave. The frequency will be higher the faster you're going. Better not be going too fast, because the policeman can measure your speed to a fraction of a mile per hour using this method - probably more accurately than your speedometer, in fact.

Johann Christian Doppler (1803-1853) first demonstrated the effect using sound waves. But we see a similar effect with light waves. On Earth the effect is so tiny that we normally don't notice it. But when we study the stars, we can get a lot of mileage out of the Doppler Effect.

Answer 4

This is not a social science question.