Calculating Magnitude of Vector Product of Two Vectors

In summary, the magnitude of the vector product of two vectors can be calculated using the formula ||<strong>A</strong> x <strong>B</strong>|| = ||<strong>A</strong>|| ||<strong>B</strong>|| sinθ, where θ is the angle between the two vectors and ||<strong>A</strong>|| and ||<strong>B</strong>|| represent the magnitudes of the two vectors. The direction of the vector product is determined by the right-hand rule, with the thumb pointing in the direction of the product when the fingers curl from vector <strong>A</strong> to vector <strong>B</strong>. The magnitude of the vector product can be negative if the angle between the two
  • #1
dmsgo89
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0

Homework Statement


For the two vectors in the figure , find the magnitude of the vector product lAl x lBl.
http://session.masteringphysics.com/problemAsset/1040325/3/yf_Figure_1_29.jpg

Homework Equations


lAl*lBl=lAl*lBlsin(alpha)


The Attempt at a Solution



2.8cm * 1.9cm * cos(60) = 2.66cm^2

2.8cm * 1.9cm * cos(120) = -2.66cm^2

Since they made two 60 degree, I thought the alpha was 60 but I got wrong.

Then, I came up with the 120 degree, however it is also wrong.

Where did I do wrong?

Please help me..
 
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  • #2
Why do you use cosine 120 degrees instead of sine?

ehild
 

1. What is the formula for calculating the magnitude of the vector product of two vectors?

The magnitude of the vector product of two vectors A and B is given by the formula ||A x B|| = ||A|| ||B|| sinθ, where θ is the angle between the two vectors and ||A|| and ||B|| represent the magnitudes of the two vectors.

2. How do I determine the direction of the vector product?

The direction of the vector product is perpendicular to both vectors A and B, following the right-hand rule. This means that if you curl the fingers of your right hand from vector A to vector B, your thumb will point in the direction of the vector product.

3. Can the magnitude of the vector product be negative?

Yes, the magnitude of the vector product can be negative if the angle between the two vectors is greater than 90 degrees. This indicates that the vectors are pointing in opposite directions.

4. How do I calculate the vector product of two vectors in three-dimensional space?

The formula for calculating the vector product in three-dimensional space is ||A x B|| = (aybz - azby)i + (azbx - axbz)j + (axby - aybx)k, where A = (ax, ay, az) and B = (bx, by, bz).

5. Can the magnitude of the vector product be greater than the magnitudes of the two original vectors?

Yes, the magnitude of the vector product can be greater than the magnitudes of the two original vectors if the angle between them is less than 90 degrees. This indicates that the vectors are pointing in the same direction, resulting in a larger magnitude for the vector product.

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