nWhat are four key features of our solar system that any theory of solar system formation must be able to explain

There are vast numbers of asteroids and comets.

Explanation:

There are clear patterns to the rotation and orbits of large bodies in the solar system.

There are a few notable "exceptions to the rules."

Planets fall into two major categories.

acceleration = (change in speed) / (time for the change)

change in speed = (20-120)= -100 m/s.

1.5 min = 90 sec

acceleration = -100/90 = -1.11 m/s^2.

we don't care about the 150kg or the 2,500 meters. they don't make any difference.

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this is poiselle's equation from fluid mechanic in physics. mech eng