The Hγ Line Has a Wavelength of 434

question 14

Multiple Choice

The Hγ line has a wavelength of 434.0 nm when observed in the laboratory. If the Hγ line appears in the spectrum of a star moving away from you, at what wavelength will you observe the line?

• A) less than 434 nm
• B) 434.0 nm
• C) greater than 434 nm
• D) the wavelength depends on the composition of the star

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Definitions:

Metering Valve

Used on vehicles equipped with hydraulic front disc and rear drum brakes to improve brake balance; holds off application pressure to front brakes until pressure builds in the hydraulic circuit to move the rear shoes into contact with the brake drums.

Proportioning Valve

A hydraulic brake valve used on vehicles equipped with front disc and rear drum brake. Its function is to reduce application pressure to the rear drum brakes to prevent premature lockup under severe braking.

Proportioning Valve

A valve in a vehicle's brake system that modulates the pressure to the rear brakes to prevent them from locking up during braking.

Rear Wheel Lock-up

A dangerous condition where the rear wheels of a vehicle cease to rotate while in motion, often leading to loss of control.