What Is the Tully-Fisher Relation

question 43

Multiple Choice

What is the Tully-Fisher relation?

• A) The more distant the galaxy, the greater is the recessional velocity.
• B) The brighter the Cepheid, the longer is the pulsation period.
• C) The more distant the galaxy, the fainter it appears.
• D) The brighter the galaxy, the wider is the 21-cm radio emission line.

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Definitions:

Covalent Bonds

Chemical bonds formed by the sharing of electron pairs between atoms, creating a stable balance of attractive and repulsive forces.

Negative Charge

A characteristic of a particle or object indicating it has more electrons than protons.

Protons

Positive-charged particles present in the core of an atom, known as subatomic particles.

Electrons

Subatomic particles with negative charge, found in all atoms and acting as the primary carrier of electricity in solids.