Lab #3 Questions

1. The measured velocities and the results of the Stoke's Law calculations were not at all in agreement.  Once the tests using particles that were either not round or larger than the Stoke's Law formula was designed to test, we are left with two tests, a .025 diameter particle of quartz in 100 cm of water.  The first test at a water temperature of 26º Celsius yielded a measured result of 3.58 cm/s.  The Stoke's Law result was 6.517, nearly twice as high as the actual results.  The second test used a water temperature of 30º C, and the measured result was 3.81 cm/s, again nearly half of the Stoke's Law result of 7.115.  These discrepancies are high enough that I would call the two not in agreement at all.

2. 

Lab #3

Laboratory #3 ~ Stoke's Law

CALCULATIONS & DATA

Velocity of a falling particle: Velocity = distance ÷ time

Stoke's Law: VO = (Ps - Pw)g(D⋄D) / 18μ

Space Weather

SPACE WEATHER is NASTY

Blue Planet

Recent space missions have driven home how isolated and self-contained our little blue planet is, and how beautiful.  But the earth is alive, churning with wild and violent processes that sweep constantly over the earth.  Some, like the Deluge that formed the oceans took place slowly, over a billion years.  Forces of erosion whittle away terrain millennium by millennium.  Others, like the withering of live-giving Lake Chad happen over generations.  Earthquakes and hurricanes carve swaths of destruction in mere days.  But all of these events make dramatic alterations to the land and the life which relies on it.

But all of the mighty forces of the earth have counterbalances.  Our planet is an incomprehensibly complex network of relationships and restorative systems.  Plants and animals form symbiotic relationships.  Geography taken away by erosion is restored by volcanic activity.  The very plates of the crust are constantly recycled, melted into the mantle as new rock takes their place.  Land damaged by storms quickly regrows life.  No species can become dominant and wipe out all others...  except for one.

          There is one force on earth that is one of the most destructive the planet has ever seen, and it has no counterbalance.  That is the works of man.  The work we have done already is not quickly reversible.  We have poisoned major rivers like the Mississippi and Yangtze.  We have destroyed the ecosystem of the island of Madagascar, and are in the process of deforesting the Amazon basin, at the price of one-hundred animal species driven extinct a day.  We emit dangerous gases which neutralize the protective ozone layer.

          But as noted, our planet is isolated and self-sustaining not by choice.  We must attempt to curb these destructive habits, to practice recoverable changes as civilization grows, or we will find ourselves stranded on the ruins of our formerly Blue Planet.

Abstract Outline

Blue Planet:

1.  The earth is a dynamic, active and violent place.  Things like volcanoes, tectonics, climate change, hurricane and earthquakes are sweep wide changes across the planet with some frequency.

2.  The earth's changes are recoverable, and it has complex systems of redundancies, symbiosis and mechanics designed to just that.  Tectonics, symbiotic relationships, and species' dependencies on the land are examples of this.

3. Human beings make changes as sweeping and violent as earth's natural storms.  Yet, we do not bother with recovery.  We will run into trouble if this pattern continues.  Big trouble.