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Deals with multiples of 360 degrees.

Right except for the sign.

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Requires answer to three significant digits for full credit.  Gives 3/4 credit if answer is accurate to 2sf. and 1/4 credit if 1sf

Find the sum of two 2-dimensional vectors, graphically and exactly using the parallelogram rule.

Trigonometric (Exact) Solution

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Use law of cosines/sines to find the following values, exactly. Give all answers to three significant digits.

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$\\theta_A$ = [[0]]

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$\\theta_B$ = [[1]]

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$\\theta_R$ = [[2]]

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$|\\textbf{R}|$ = [[3]]

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$\\theta_x$ = [[4]]

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Force B

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Direction of force A, based on Ax and Ay.

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Magnitude of force B,  Magnitude of A is twice this value.

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Force A

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Vector Addition: $\\textbf{R}$ = $\\textbf{A}$ + $\\textbf{B}$

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Find the magnitude and direction of resultant $\\textbf{R}$ when $A$ = {2 FB} {units} and $B$ = {FB} {units},

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by using triginometry.

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Procedure:

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1. Draw a neat diagram and label the unknown side and angles.
2. \n
3. Determine the angle opposite the unknown force $\\textbf{R}$.
4. \n
5. Use law of cosines to determine the magnitude $|\\textbf{R}|$
6. \n
7. Use either the law of sines or cosines to determine the other two angles.
8. \n
9. Use the angles you have found to determine the direction of force $\\textbf{R}$ from the x-axis.
10. \n
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