Vector distance and angle question

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KevinFan
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Homework Statement


Instructions for finding a buried treasure include the following: Go 65.0 paces at 249deg, turn to 134deg and walk 134 paces, then travel 101 paces at 168deg. The angles are measured counterclockwise from an axis pointing to the east, the +x direction. Determine the resultant displacement from the starting point. Enter the distance (without units) and the angle relative to the positive x-axis.

Homework Equations

The Attempt at a Solution


For the resultant displacement, I got R=sqrt(V1^2+V2^2+V3^2)= sqrt(65^2+249^2+134^2)=179.94
For the angle, I honestly don't have any clue...
 
KevinFan said:

Homework Statement


Instructions for finding a buried treasure include the following: Go 65.0 paces at 249deg, turn to 134deg and walk 134 paces, then travel 101 paces at 168deg. The angles are measured counterclockwise from an axis pointing to the east, the +x direction. Determine the resultant displacement from the starting point. Enter the distance (without units) and the angle relative to the positive x-axis.

Homework Equations

The Attempt at a Solution


For the resultant displacement, I got R=sqrt(V1^2+V2^2+V3^2)= sqrt(65^2+249^2+134^2)=179.94
For the angle, I honestly don't have any clue...
On what basis do you think that your equation gives the correct displacement?
 
Chestermiller said:
On what basis do you think that your equation gives the correct displacement?
I am not too sure...
Maybe this equation is for distance. Could you please tell me what is the correct method for solving this question?
 
1. Have you drawn a diagram? If so, let's see it.
2. Do you know how to resolve a vector into its x and y components?
 
Chestermiller said:
1. Have you drawn a diagram? If so, let's see it.
2. Do you know how to resolve a vector into its x and y components?
Here is a rough diagram that I drawn.
I know how to resolve vector into x and y components.
 
Attachments
  • Pencil sketch on lined notebook paper of three vectors drawn as arrows meeting at right-angled axis crossings, labelled 101, 134 and 65, with angles 168 degrees, 134 degrees and 244 degrees marked at the junctions.
    image1.JPG
    32.8 KB · Views: 496
KevinFan said:
Here is a rough diagram that I drawn.
I know how to resolve vector into x and y components.
Very nice. Now what are the x and y components of each of the three successive displacement vectors?
 
Chestermiller said:
Very nice. Now what are the x and y components of each of the three successive displacement vectors?
Is the displacement the sum of x components vector?
 
KevinFan said:

Homework Equations

.

Ah, well there's your problem. Could you cut and paste the vanilla equations from the textbook, that you think should be applied to the specifics of the problem, into that big blank section ? Maybe annotate with what they are.

Nice diagram: you clearly understand the parameters as given (except that last angle thing, which arc is drawn from the y-axis instead of the x... but the line is pointed in the right direction)
 
KevinFan said:
Is the displacement the sum of x components vector?
The total displacement is the magnitude of the vector drawn from the origin to the tip of the final (3rd) vector.