Finding an angle in the direction of displacement

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SUMMARY

To find the direction of Frank's total displacement vector, he hiked 5.8 km East, 9.1 km North, and 1.5 km West. The correct approach involves calculating the resultant vector using x and y coordinates, where East is positive x and North is positive y. The final displacement vector can be determined using trigonometric functions to find the angle from the x-axis. The angle should be expressed in degrees North of East, with a precision of 0.2 degrees.

PREREQUISITES
  • Understanding of vector addition in two dimensions
  • Knowledge of trigonometric functions (sine, cosine, tangent)
  • Ability to convert distances into coordinate systems
  • Familiarity with angle measurement and notation
NEXT STEPS
  • Learn how to calculate resultant vectors using the Pythagorean theorem
  • Study the use of trigonometric functions to find angles in right triangles
  • Explore coordinate transformations in physics and engineering contexts
  • Review compass direction conventions and their applications in navigation
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Students studying physics or mathematics, educators teaching vector analysis, and anyone interested in navigation and displacement calculations.

ilovedeathcab
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finding an angle in the direction of displacement (resolved)

Frank hikes 5.8 km East, 9.1 km North, and 1.5 km West. Find the direction of his total displacement vector. Give your answer in terms of degrees North of East. Make sure you do the following in your answer:

* DO NOT write out a description of your angle. The text "North of East" is not necessary.
* DO NOT put your answer in terms of "East of North". This will be marked as incorrect.
* DO NOT indicate units. We will assume degrees.
* make your answer correct within 0.2 degrees
* put your answer in a form like one of these:
o #.#
o ##.#
--------------------------------------------------------------------------
i tried and measured this, converting km to cm, and measured with protractor, and got 67 degrees north of east. then i tried again, because my measurements were off, but it wouldn't accept 69 degrees. can't find what i am doing wrong (??)
 
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ilovedeathcab said:
Frank hikes 5.8 km East, 9.1 km North, and 1.5 km West. Find the direction of his total displacement vector. Give your answer in terms of degrees North of East. Make sure you do the following in your answer:

* DO NOT write out a description of your angle. The text "North of East" is not necessary.
* DO NOT put your answer in terms of "East of North". This will be marked as incorrect.
* DO NOT indicate units. We will assume degrees.
* make your answer correct within 0.2 degrees
* put your answer in a form like one of these:
o #.#
o ##.#
--------------------------------------------------------------------------
i tried and measured this, converting km to cm, and measured with protractor, and got 67 degrees north of east. then i tried again, because my measurements were off, but it wouldn't accept 69 degrees. can't find what i am doing wrong (??)

Try considering the distances in terms of x, y coordinates (I'd recommend East = x positive, North = y positive). Find the final position relative to the start point (0,0). You now have a right triangle, use that to find the angle mathematically.

I'm not sure I understand why there all the restrictions on description of the angle. Traditional compass directions consider North to be 0º, East to be 90º, for what it's worth.
 

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