Via the Rotation Curve Method, We Can Estimate the Mass $\pi$

question 78

Multiple Choice

Via the rotation curve method, we can estimate the mass of galaxies like M31 from

• A) Doppler shifts of material at the edge of its disk and computing P = 2 \(\pi\)r/v.
• B) the distances of the Doppler shift points from its center.
• C) both answers A and B
• D) It is impossible to estimate the mass of M31.

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Definitions:

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Abrupt and uncomfortable transitions from a higher to a lower gear in a vehicle's transmission, often indicating a problem.

Manual Selector Linkage

The mechanical connection that enables the driver to select gears manually in a vehicle, often connected to the transmission.

Transmission Fluid

A lubricant used in the transmission system of a vehicle to cool and protect the moving components.

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A substance applied to gaskets in order to enhance their sealing capabilities, preventing leaks between component interfaces.