Finding tangential acceleration of a rotating disk

AfronPie · Aug 8, 2017

Homework Statement

Attached.

Homework Equations

Tangenital acceleration=r*alpha

3. The Attempt at a Solution
I thought it was just simply r*alpha=2*20=40 (choice A), but the answer key says choice B. I'm not really sure where I could have went wrong or its possible that there is a mistake in the answer key.

Multiple-choice physics problem text: a circular disk of radius 2.0 m rotates from rest with angular acceleration 20.0 rad/s^2; asks tangential acceleration at the edge when angular speed is 1.0 rev/s. Choices A) 40 m/s^2, B) 79 m/s^2, C) 110 m/s^2, D) 120 m/s^2, E) zero m/s^2.

Any insight would be very helpful. Thanks.

BvU · Aug 8, 2017

Stick to answer A. Key's wrong.

CWatters · Aug 8, 2017

I think you are correct..

http://spiff.rit.edu/classes/phys211/lectures/tang/tang_all.html

AfronPie · Aug 8, 2017

BvU said:

Stick to answer A. Key's wrong.

Thanks.

scottdave · Aug 8, 2017

I calculate 79 m/s² for the centripetal acceleration (towards the center).

Finding tangential acceleration of a rotating disk

Homework Statement

Homework Equations

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