NASA uses the famous "Vomit Comet," a KC-135 cargo plane, to provide astronauts and scientiest a simulated zero-gravity environment. The plane flies in a parabolic arc, at the top of which a passenger feels "weightless." This is because
A. the acceleration of the passenger is nearly zero at the top of the arc
B. the gravitational force exerted by Earth on the passenger is nearly zero at the top of the arc
C. the force exerted by the floor of the plane on the passenger is nearly zero at the top of the arc
D. a and b
Answer: C. the force exerted by the floor of the plane on the passenger is nearly zero at the top of the arc
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During various stages of evolution, low mass stars (like the Sun) differ significantly from high mass stars. How do they differ in terms of observational properties while Main Sequence stars?
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