A Boxcar Without a Front or a Back Is Moving

question 28

Multiple Choice

A boxcar without a front or a back is moving toward the right. Two electrons move through the boxcar, one moving from back to front toward the right, the other moving from front to back toward the left. According to me, each electron is moving with a speed of 0.8c, and the boxcar is moving with a speed of 0.6c. A passenger in the boxcar records how long it takes each electron to pass from one end of the boxcar to the other end. According to the passenger, which took less time?

• A) the electron going from front to back
• B) the electron going from back to front
• C) Since nothing can go faster than light, an electron cannot move toward the left with a speed of 0.8c through a boxcar moving toward the right with a speed of 0.6c.
• D) They both took the same time.

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Definitions:

Vitamin D

A fat-soluble vitamin that helps regulate calcium and phosphorus levels in the body, crucial for healthy bones and teeth.

Eicosanoids

Signaling molecules made from fatty acids, instrumental in inflammatory responses and other physiological functions.

Plasma Membrane

The two-layered lipid structure that acts as the cell's exterior limit, controlling the movement of materials into and out of the cell.

Denaturation

A process in which proteins lose their native shape and function due to external stress, such as heat or acidic conditions.