1. and 2.
Within all of the above force calculations, I incorrectly attempted to convert pounds to Newtons and ended up with lbs m/s^2 which still is not the correct units for Newtons. Within the professor's blog post, I missed the section in which he declared to US measurements. This means all of my calculations are off by a factor of 9.8. Dividing each of the above calculations by 9.8 gives the force on each member in pounds.
3.
4.
The results I received from the hand analysis closely relate to that of the Truss Designer program. The values are slightly off due to the inability to define specific lengths of members along with angles within the Truss Designer program. I converted to the 20 pounds of weight to Newtons of force by simply using F=ma. F=20lbs(9.81m/s^2)~196N. Within the Designer, it only allows you to set in increments of 5N so I chose 195 being the floored value of 196.
5. and 6.
This is a rough design as to what our KNEX bridge looks like, and under the weight of the 20lbs. designated to my respective group/last name. The bridge appears to be under much stress directly in the middle and could possibly use some more support there. The oscillating pattern of tension and compression throughout the center members is a very fascinating thing since the simpler design calculated above has both middle members being in tension. Using the program shows me where the most force is being placed on our group's bridge and to where the downfall may come if it were only a 2-d test.
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