A Spaceship, Moving Away from the Earth at a Speed

question 52

Multiple Choice

A spaceship, moving away from the Earth at a speed of 0.9c, shines a green laser backwards at Earth. An observer on Earth would see the light arriving at a speed of

• A) 0.1c and with an inverted frequency.
• B) more than c but less than 1.9c.
• C) c but at a shorter wavelength.
• D) c but at a smaller frequency.
• E) 1.9c and with a shorter wavelength.

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Definitions:

Endodermal

Pertaining to the innermost layer of the three primary germ layers in the very early embryo, which gives rise to the digestive and respiratory systems among others.

Ectodermal

Pertaining to the ectoderm, the outermost layer of the embryo, giving rise to the nervous system, skin, and various sensory organs.

Germ Layers

The three primary layers of cells (ectoderm, mesoderm, and endoderm) in the early embryo from which all tissues and organs develop.

Ectoderm

The outermost layer of cells or tissue of an embryo in early development, giving rise to the skin and nervous system.