Understanding Vector Addition in Acceleration Problems

[PsychonautQQ]

Homework Statement

http://grephysics.net/ans/0177/23

The answer to this problem is confusing me.
So you can calculate the normal acceleration and tangential acceleration to each by equal and 90° apart from each other, so their final vector has an angel of 45°. However, if the speed travels in the same direction as the tangential acceleration, wouldn't the angel between the TOTAL acceleration vector and the velocity vector be 22.5° ?

 

[vela]

No, how'd you come up with 22.5 degrees? Try drawing a picture.

 

[PsychonautQQ]

because the total acceleration vector is at a 45 degree angel, and the velocity vector would be on an axis, so wouldn't between them be 22.5?

 

[verty]

Homework Statement

http://grephysics.net/ans/0177/23

The answer to this problem is confusing me.
So you can calculate the normal acceleration and tangential acceleration to each by equal and 90° apart from each other, so their final vector has an angel of 45°. However, if the speed travels in the same direction as the tangential acceleration, wouldn't the angel between the TOTAL acceleration vector and the velocity vector be 22.5° ?

Speed is a scalar, it doesn't have direction. It is the velocity's magnitude and measures how quickly the particle is moving regardless of the direction of travel.

 

[vela]

because the total acceleration vector is at a 45 degree angel, and the velocity vector would be on an axis, so wouldn't between them be 22.5?

No, it wouldn't. Did you draw a picture? What's the angle between the tangential acceleration and the velocity?

 

[PsychonautQQ]

No, it wouldn't. Did you draw a picture? What's the angle between the tangential acceleration and the velocity?

0? Arn't they the same?