What Two Quantities Did Edwin Hubble Plot Against Each Other

question 92

Multiple Choice

What two quantities did Edwin Hubble plot against each other to discover the expansion of the Universe?

• A)velocity and distance
• B)luminosity and distance
• C)velocity and temperature
• D)luminosity and temperature
• E)age and distance

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Definitions:

Trolley Valve

A valve used in air brake systems on trucks and trailers, allowing the driver to control the trailer brakes independently.

Service Application Valves

Valves used in the maintenance and repair process of various systems, allowing for the control or direction of flow during service.

Spike

A sudden surge in hydraulic pressure or electrical voltage. Also a slang term meaning the tractor steering column mounted, trailer service brake valve.

Tractor Protection Valve (TP)

A safety device on tractor-trailer combinations that protects the air brake system from losing air pressure in the event of a trailer breakaway or leak.