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Let A represent any nonzero vector. Why is A→A a unit vector, and what is its direction? Ifθis the angle that Amakes with the +x-axis, explain whyA→Ais called the direction cosinefor that axis.

Short Answer

Expert verified

Magnitude is 1 and its direction is the same as the vector, the quantity is called aunit vector.

Step by step solution

01

 Unit Vector and its direction

The vector's various coordinates are presented here.

A vector having themagnitude of 1and no units is called a unit vector. Its sole function is to point, or to describe a spatial direction.

For many formulas involving vector components, unit vectors are a useful notation.

A unit vector dn pointing in the positive x-axis and a unit vector en pointing in the positive y-axis can be defined in a xy-coordinate system.

We know that in coordinates, the x component of a vector comes first, followed by the y component.

To calculate the angle of the vector with respect to the x axis, just multiply the y component by the x component and then take the inverse of that result.

This will tell you thevector's angle with the x axis.

02

Unit Vector and direction cosine

To determine: The justification behind the unit vector's name, as well as its direction.

The x-axis was given the moniker direction cosine for a purpose.

As its magnitude is 1 and its direction is the same as the vector, the quantity is called a unit vector

Because it equals the angle formed by the vectors with the positive x-axis, the quantity is called direction cosine for x-axis.

The quantity has a magnitude of one. As a result, it is referred to as a unit vector. Calculate the quantity's value.

The vector's angle with the positive x-axis is Cosine direction. As a result, the quantity is known as x-axis direction cosine.

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