BFPM Practicum

Objective: Determine the weight of an object hanging from two objects at unequal angles to each other. 

Step 1: Collect known data. We know the tension of each rope (FT1 = 2.2 Newtons, and FT2 = 1 N) and angle measurements.
Step 2: Draw Free-Body Diagram of the situation (include quantities).
Step 3: If a force's vector does not align with the axes, than add a vector for each force so that it does align. So create FTx1 and FTx2, FTy1 and FTy2.
Step 4: Angle Measurements: ∠FT1 and FTy = 20º, ∠FT1 and FTx = 70º, ∠FT2 and FTy = 55º, ∠FT2 and FTx = 35º
Step 5: Use Cosineθ = Adj/Hyp which FT1 is the Hypotenuse and FTy is the Adjacent for the first part. For the second part of the problem, Use Cosineθ = Adj/Hyp which FT2 is the Hypotenuse and FTy2 is the Adjacent.
Step 6: Plug in the measurements into one of the formulas. ∠FT1 and FTy = 20º, so Cos(20º)=Adj/2.2. ∠FT2 and FTy = 55º, so Cos(55º) = Adj/1. 
Step 7: Cos(20º)=Adj/2.2. To calculate this part of the weight, just multiply Cos(20º) with 2.2 and you should calculate a number close to 2.067 Newtons.
Step 8: Cos(55º) = Adj/1. To calculate this part of the weight, just multiply Cos(55º) with 1 and you should calculate a number close to .573 Newtons.
Step 9: To calculate the weight of the object, just add the two quantities (2.067 Newtons and .573 Newtons) and you should calculate a number close to 2.64 Newtons.