Vectors Via the Calculator (For Non-Math Students)

Junievicz, Alex Gordon Tech

Objective To be able to resolve vector problems without knowledge of algebra or math. Give the student with poor math a chance of passing the course. Apparatus Needed Scientific Calculator with Sin, Cos, and Tan. A Ball of yarn for demonstrating vector-Soft so as not to hurt a student hit with it. Optional Overhead and overlay of vector-triangle. Recommended Strategy First, using the yarn tossed to the class, demonstrate the difference between regular and polar coordinates and that a vector must have a vertex and an angle. A sign on the string may help define the vector. Next, use a worksheet that explains the steps of using the calculator. (Caution there are some calculators that you enter sin then the angle, where on most you enter the angle and then the function.) Be sure to include the use of the bracket (-). Also before demonstrations, check your calculator to be sure it is in the correct mode by using a known angle i.e., 30 degrees. DO NOT USE the Pythagorean theorem, but use the Trig functions. Demonstrate resolving two (or more) vectors using the Horizontal, --saving in memory- -calculating the Vertical, dividing, and using the arc-tan to get the angle. Vector A is 2 units at 30 degrees, Vector B is 4 units at 120 Degrees. Find the resultant angle, and length. ----Be sure the memory is cleared----Save Horizontal in memory--- ((2(30Cos))+(4(120Cos))m+Divide(2(30Sin)+(4(120Sin))ArcTan Gives the angle now to find the magnitude (Write down the angle found) Using the trig formula R = Adj / Cos Find R Mr divided angle previously found Cos = Vector Magnitude. Have the student copy an example as it is worked out for his own notes. A pass out sheet double size 11 x 16 with references and examples functions well.
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