The Cosmic Microwave Background Radiation Is Not Uniform Over the Sky

question 111

Multiple Choice

The cosmic microwave background radiation is not uniform over the sky: It is slightly hotter toward the constellation Leo and slightly cooler in the opposite direction toward Aquarius.Why?

• A) The background radiation really is uniform;the observed difference is due to Earth's motion through the universe.
• B) That is the way the universe began: hotter in one direction and cooler in the other.
• C) The difference is probably a statistical fluctuation,and therefore not real.
• D) Earth is slightly off-center in the universe,so one side of the universe is a bit closer and the other side is a bit farther away.

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Definitions:

Inductive Reactance

The opposition that inductors present to the flow of alternating current, due to the phase shift between voltage and current, measured in ohms.

Coil

An electrical component made by winding conducting wire around a core or forming it into a loop or series of loops, often used in inductors and transformers.

Reactance

The opposition a circuit element offers to the flow of alternating current, due to its capacitance or inductance, affecting the phase between voltage and current.

Inductive Reactance

The opposition that an inductor presents to alternating current, due to its inductance, measured in ohms.