9.14.07 Astronomy notes

# 9.14.07 Astronomy notes - -No such thing as a free force,...

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Astro notes 9/14/07 Newton’s laws: Bubonic plague Cambridge in 1665 Philosophie naturalis principia mathetmatica First law = every body continues in a state of rest or in a state of uniform motion in a straight line unless it is compelled to change that state by a force acting on it. Force = push or pull. - “Instantaneous” - Continuous (gravity, friction) Second law = when a force F acts on a body of mass m , it produced in it an acceleration a equal to the force divided by the mass. A = F / m; F = m*a - Units of force = N (Newton) = kg * m / s^2 Third law = to every action there is an equal and opposite reaction
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Unformatted text preview: -No such thing as a free force, they are always balanced Gravity Continuous force Baseball example: NII: F [E->BB] = m[BB]*a[BB] NIII: baseball pulls on earth, as well as vice versa. Newtons law of universal gravitation : Thought experiment: there exists some speed at which something will constantly fall around the earth (orbit). From planetary data: high velocity, high acceleration to keep it in orbit-Distance small, high velocity. Farther planets go slower F = [m1m2 / r^2]G G = newtons gravitational constant = 6.67 E -11 Nm^2/kg^2...
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## This note was uploaded on 09/24/2009 for the course ASTR 101 taught by Professor Christiansen during the Fall '08 term at UNC.

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