| MadSci Network: Physics |
Hello Timothy: Since your questions are very specific, I will attempt to answer each one separately. Q. does the thickness of air (for example at a high altitude vs a low altitude) change air resistance? A. Absolutely. Air is a mixture of gases: primarily nitrogen and oxygen. At low altitudes, the molecules are packed much tighter than at higher elevations. The closer the molecules are to one another, an object moving through encounters the more resistance. This resistive force is called aerodynamic drag. As altitude increases, the more loosely molecules are packed and the force due to drag diminishes. This is one reason why modern aircraft fly at high altitudes. Visit this website for more information: http://www.sprl.umich.edu/PHAYS/Chap_3/Chap_3.html Q. are there large differences between mediums of resistance? A. Yes. Air is thin as compared to water, but their characteristics are similar. Both are called fluids because their physical properties are alike. Q. can the angle of your object affect how the medium of resistance works? A. It depends. If the medium is homogeneous, the resistance is constant. If heterogeneous, the resistance varies with respect to the relative density. Example: As an airplane climbs the air density is reduced as function of altitude, and the drag force operating on the airplane is also reduced. The opposite effect takes place as the airplane descends to land. Q. does fall speed affect impact results? A. Very much so. The speed is a direct function of the object mass and the square of the relative speed of travel. Q. does height affect impact? A. Because of earth's gravitational force, when an object is dropped, it will accelerate at the rate of 32 feet/second squared. They higher the fall, the harder the impact. However, due to aerodynamic drag, the terminal speed at impact depends on the object's mass and shape. In vacuum, if a feather and a rock are dropped from a tower, they will impact the ground at the same exact time. In atmosphere, the rock will hit the ground much faster and harder than a feather. Q. can angle affect impact results? A. Yes. If the fall is perpendicular to the impact medium, all energy is dissipated on impact. When the angle decreases from 90 degrees, the energy is partly dissipated on impact and part retained to continue the trajectory. Look-up on the Internet: http://www.pre-engineering.com/ScalarsAndVectors.html Q. does an objects's mass affect impact results? A. Yes. Same formula that Albert Einstein developed before I was a kid. Energy= 1/2 mass times velocity squared. Look-up on the Internet: http://www.flic.net/~saa/Professional/equations.html Q. does an object's volume affect impact on an object? A. We have to make the assumption that the object is smaller than the impacting surface. In this case, the only effect would be the drag force induced by aerodynamic or hydrodynamic effects. The drag would slow the object down prior to impact. Otherwise, things can get pretty neat, especially at the size of sub-atomic particles. I suggest you visit on the Internet: http://particleadventure.org/ I hope your questions have been satisfied. Your MAD.SCI Micro.
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