# Basic Conceptual Question regarding a tangential/radial accel formula [Pythagorean?]

## Homework Statement

I'm reviewing a chapter relating linear and angular kinematics, and I came across this equation.. why does it work and where does it come from? I can't seem to find anything in the textbook explaining it.

## Homework Equations

a = sqrt( (tangential acceleration)2 + (radial acceleration)2 )

## The Attempt at a Solution

I know all of the basics quite well, I just don't understand where this formula came from! All help will be very appreciated. Please dont go too in depth and waste your time! A simple answer should definitely suffice! Thank you! .

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Additionally, why does the square root of the two squares of acceleration equal the total. I'm not exactly sure how you would go about "Drawing a triangle" or anything like that.

Hi AJBalbirnie
The tangential acceleration and radial acceleration are orthogonal to each other. they are the components of the total acceleration.
So the triangle you are looking for is: the hypotenuse is the total acceleration and the other sides are the tangential and radial components

Thank you. The issue is more visual to me than actually knowing the sides of the triangle though. Thanks.

The orthogonal part makes it all go together though. Thank you.

PhanthomJay