Fred and Joanne Both Measure the Length of a Particular

question 95

Multiple Choice

Fred and Joanne both measure the length of a particular spaceship to be 100 m when it is on Earth. Joanne then gets into the spaceship and, after visiting the Moon, hurtles past Earth at a speed close to the speed of light. Fred, still on Earth, measures the length of the moving spaceship to be about 90 m. At the same time, Joanne (using her own meterstick) measures the length of the spaceship to be

• A) about 90 m because of the motion of the spaceship.
• B) 100 m because she is "at rest" on the spaceship.
• C) It cannot be concluded from the information given.
• D) about 110 m because both she and the spaceship are moving.

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Definitions:

Protons

Positively charged subatomic particles found in the nucleus of an atom.

Neutrons

Subatomic particles found in the nucleus of an atom, carrying no electric charge.

Thylakoid Membrane

A membrane-bound compartment inside chloroplasts and cyanobacteria, essential for the light-dependent reactions of photosynthesis.

ATP

An essential nucleotide that serves as the main energy source for many cellular processes, functioning in energy transfer within cells.