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Ch 12: Rotation of a Rigid Body
Chapter 12, Problem 12

Evaluate the cross products and A ✕ B and C ✕ D. Diagram showing vectors E and F with magnitudes 3 and 4 at a 30° angle.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Cross Product

The cross product of two vectors results in a third vector that is perpendicular to the plane formed by the original vectors. It is calculated using the formula A × B = |A||B|sin(θ)n, where θ is the angle between the vectors and n is the unit vector perpendicular to the plane. The magnitude of the cross product represents the area of the parallelogram formed by the two vectors.
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Vector Magnitude

The magnitude of a vector is a measure of its length and is calculated using the Pythagorean theorem for two-dimensional vectors. For a vector represented as A = (Ax, Ay), the magnitude is given by |A| = √(Ax² + Ay²). In the context of the question, the magnitudes of vectors E and F are 3 and 4, respectively, which are essential for calculating their cross product.
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Angle Between Vectors

The angle between two vectors is crucial for determining the sine component in the cross product formula. In this case, the angle is given as 30°, which affects the magnitude of the resulting vector from the cross product. Understanding how to find and use this angle is key to solving problems involving vector operations.
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