Finding the Angle Between Vectors A & B

In summary, Vectors A and B have equal magnitudes of 5.12 and their sum is the vector 6.37j. The angle between A and B cannot be determined using the cosine law as the given values do not result in the correct answer. Further clarification is needed.
  • #1
Rail24
2
0

Homework Statement



Vectors A and B have equal magnitudes of 5.12. If the sum of A and B is the vector 6.37j, determine the angle between A and B.

Homework Equations



Cosine law?

The Attempt at a Solution



I attempted to do this using the cosine law which I thought made sense but 103 degrees is not the right answer..
 
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  • #2
when i use the cosine equation:
cosA = (b^2 +c^2 - a^2)/2bc
A = cos-1[(b^2 +c^2 - a^2)/2bc]
i did not get 103 degrees... id suggest to check your numbers??
 
  • #3
You got 77 degrees correct?
I just subtracted from 180 because the angle I assume is tail to tail.

I also tried 77 degrees (or rather 76.9 degrees) and it's also not the answer.
 

1. What is the definition of "vectors"?

Vectors are mathematical quantities that have both magnitude and direction. They are commonly represented by an arrow pointing in the direction of the vector, with the length of the arrow representing the magnitude.

2. How are vectors represented mathematically?

Vectors can be represented by a set of coordinates or components, typically denoted by A = (ax, ay, az). The components indicate the magnitude of the vector in the x, y, and z directions, respectively.

3. What is the formula for finding the angle between two vectors A and B?

The formula for finding the angle between two vectors A and B is cos θ = (A · B) / (|A| ⋅ |B|), where θ is the angle between the vectors, A · B is the dot product of A and B, and |A| and |B| are the magnitudes of A and B, respectively.

4. Can the angle between vectors be negative?

No, the angle between vectors cannot be negative. It is always measured in a counterclockwise direction from the first vector to the second vector, and therefore, it will always be between 0 and 180 degrees (or 0 and π radians).

5. How is the angle between vectors used in real-world applications?

The angle between vectors is commonly used in physics, engineering, and navigation to determine the direction and magnitude of forces, velocities, and displacements. It is also used in computer graphics and animation to create realistic movements and rotations.

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