How Do Astronomers Obtain an Estimate of the Amount of Mass

question 140

Multiple Choice

How do astronomers obtain an estimate of the amount of mass that is inside the Sun's orbital path in the Milky Way Galaxy?

• A) by counting stars, assuming an average stellar mass, and calculating the total mass
• B) by observing the bending of light from distant galaxies as the light passes near the center of the Milky Way
• C) by observing the movement of the Galaxy toward neighboring galaxies because of mutual gravitational attraction
• D) by applying Kepler's law to the motion of the Sun and other nearby stars

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Definitions:

Long-Run Adjustment

The process by which firms adjust their production capacity and input usage to new market conditions over time, beyond short-term fluctuations.

Returns To Scale

Rate at which output increases as inputs are increased proportionately.

Increasing Marginal Product

A situation where each additional unit of input results in an increased amount of output.

Economic Rents

Extra earnings above the minimum amount necessary to keep a factor of production in its current use.