How Does Gravitational Lensing Tell Us About the Mass of a Galaxy

question 27

Multiple Choice

How does gravitational lensing tell us about the mass of a galaxy cluster?

• A) Using Einstein's general theory of relativity, we can calculate the cluster's mass from the precise way in which it distorts the light of galaxies behind it.
• B) The lensing allows us to determine the orbital speeds of galaxies in the cluster, so that we can determine the mass of the cluster from the orbital velocity law.
• C) The lensing broadens spectral lines, and we can use the broadening to "weigh" the cluster.
• D) Newton's universal law of gravitation predicts how mass can distort light, so we can apply Newton's law to determine the mass of the cluster.

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Definitions:

RNA

Ribonucleic acid, a molecular substance present in cells responsible for carrying out the genetic instructions for protein synthesis.

Golgi Apparatus

Organelle consisting of sacs and vesicles that processes, packages, and distributes molecules about or from the cell.

Protein Products

Molecules generated as a result of gene expression, composed of amino acids, and play various roles in the body such as catalytic, structural, and signaling functions.

Golgi Apparatus

A cell organelle responsible for the modification, sorting, and packaging of proteins and lipids for secretion or use within the cell.