CHALLENGER'S LOST LESSONS - ER - NASA

18charge of their molecules.The teacher will use strips of filter paper 1/2"x 3" long, and aflight approved, water base ink felt tip pen. The paper will be placedin a lexan vial after adding a water drop to begin the process. Thisprevents evaporation from slowing down and stopping the processprematurely.There are parallels between the behavior of the ink moleculesin this demonstration and the behavior of the molecules of thechemicals used in the continuous flow electrophoresis (CFES) usedto process pharmaceuticals.SIMPLE MACHINESThe objective of this activity was for students to understandsimilarities and differences between the use of simple machines inspace and Earth environments. The question posed was "wouldcertain simple machines have been developed by people who alwayslived in microgravity?" Stated another way, “what are theapplications in space for simple machines like the wheel and axle,lever, inclined plane, wedge, and pulley?”The original plan called for a wooden inclined plane, a cartwith four wheels, hammer and nail, screw to be screwed into theinclined plane, and a pulley. The commander immediately vetoedthe idea of driving nails into the wood because of the potential fordamage to the Orbiter". A refresher in physics reminds one that theforces input into the hammer-nail-wood system would ultimatelyhave to be transmitted to either a crewmember or the craft. Since thegoal of this particular part of the activity was to use the hammer topull the nail, thereby demonstrating a fulcrum and lever, it wasdecided to demonstrate the lever using the 18" pry bar in the Orbitertool kit instead. Also, it was not desirable to use wood due toflammability. For some time a 4” wide folding aluminum metermeasure was considered to serve as an inclined plane and with theNewton's Laws demo, but it proved to be a stowage problem. Awedge of aluminum 10” long x 2" wide x 3" high was produced toserve as the inclined plane and wedge. It also was drilled and fitted