# Isn't the normal acceleration always towards the center?

cipotilla

See attachment

## The Attempt at a Solution

I solved the problem (on the same page as problem, written in pencil) but the direction of the acceleration that I calculated is different, I dont understand why my answer is wrong if the normal acceleration always towards the center and the tangent acceleration is suppossed to be clockwise.

#### Attachments

• Direction of acceleration.pdf
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Mentor
Yes, the radial acceleration is towards the center. But I don't see why you think your solution is different from the book's. Seems to me you are just measuring your angle from a different reference direction--they measure from the horizontal, you from the vertical.

cipotilla
Yes, the radial acceleration is towards the center. But I don't see why you think your solution is different from the book's. Seems to me you are just measuring your angle from a different reference direction--they measure from the horizontal, you from the vertical.

I think I measured from the horizontal, thats why I think my answer is different from the books, see diagram. Thanks!

#### Attachments

• Acceleration direction.pdf
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Mentor
Looks to me like your diagram is sideways, compared to the original diagram given with the problem. What you call "horizontal" appears as vertical in the original diagram.

cipotilla
You are absolutely right, drew my acceleration vectors on the right side of the pulley, where there is no conveyor belt, thats why I got confused. Ok, thanks you.