How do you find the magnitude of a vector given its x and y components?
Conditions
- The vector is defined in a 2D Cartesian coordinate system.
- The coordinate axes are orthonormal (perpendicular with the same unit scale).
- The magnitude represents the Euclidean length.
Reasoning, step by step
- Identify the x-component and y-component of the vector.
- Substitute these values into the formula .
- Square each component individually.
- Add the squared values together.
- Take the positive square root of the sum.
Example
For the vector , the magnitude is calculated as .
Common misconceptions
- Thinking that a negative component reduces the magnitude; squaring a negative number yields a positive result, so .
- Applying the formula unchanged to nonorthogonal coordinate systems.
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