Why is the right hand rule for cross product?

In summary, the direction of the cross product is determined by the right hand rule, which is a convention used to fit with the usual naming of the axes in a right-hand coordinate system. This allows for consistency and conformity in performing cross products in this space.
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so, the magnitude of the cross product represents the area or volume enclosed by any 2 or 3 vectors respectively, but what does the direction represent? i get that the general direction is one that is perpendicular to all the vectors, but what does the actual direction represent? ie, why the right hand rule? ie, why this particular direction instead of the opposite? is it just by convention or is there a particular reason?
 
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The right hand rule is just a convention. If one adopts the left hand rule everything would work the same only backwards. This is to fit with the usual naming of the axes x,y,z.
 
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To expand on what lurflurf said, it is just a convention. The coordinate system most widely used is a right-hand coordinate system. You can see for yourself by using the right-hand rule on the x and y axes.

This would lead to the z-axis point towards you if the y-axis is oriented vertically and the x-axis oriented horizontally (in the plane perpendicular to your vision).

The right-hand rule just makes all the cross products you perform in this space conform to this.
 

Related to Why is the right hand rule for cross product?

1. Why is the right hand rule used for the cross product?

The right hand rule is used for the cross product because it provides a simple and intuitive way to determine the direction of the resulting vector. It also aligns with the conventions used in physics and engineering, making it a standard method for calculating cross products.

2. How does the right hand rule work?

The right hand rule works by using the fingers of your right hand to represent the direction of the first vector and the thumb to represent the direction of the second vector. The resulting vector will then point in the direction that your palm is facing.

3. What is the significance of using the right hand instead of the left hand for the cross product?

The choice to use the right hand instead of the left hand for the cross product is arbitrary and simply a matter of convention. However, it is important to maintain consistency in using either the right or left hand rule for all cross product calculations to avoid confusion.

4. Can the right hand rule be used for all types of cross products?

The right hand rule can be used for all types of cross products, including vector cross products in 3D space and matrix cross products in linear algebra. It is a versatile method that can be applied to various mathematical concepts.

5. Are there any alternatives to using the right hand rule for the cross product?

While the right hand rule is the most commonly used method for calculating cross products, there are a few alternative methods such as the left hand rule or the index finger rule. However, these alternatives are not as widely accepted and may cause confusion in certain contexts.

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