Rotational Velocity Homework: Find Accel & Distance for Stopping Wheel

AI Thread Summary
The discussion revolves around calculating the rotational acceleration and distance a wheel travels while stopping. The initial rotational velocity is 14 rad/s, and it takes 5 seconds to stop, leading to an acceleration calculation of -2.8 rad/s². The user struggles with finding the distance the wheel rotates during this time, attempting to use an incorrect equation. Responses emphasize the importance of correctly identifying variables and ensuring unit consistency in calculations. The conversation highlights the need for users to independently verify their understanding of the relevant physics equations.
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Homework Statement


A wheel has a rotational velocity of 14 rad/s clockwise you place your hand against the wheel and the friction between your hand and the rim stops it
a) If it takes 5s to stop the wheel what is its rotational acceleration
b)How far does the wheel rotate while slowing to a stop?


Homework Equations





The Attempt at a Solution


I got A very easy just taking 14/5 but am struggling with part B
Here is what I have so far, and I know its wrong but cannot figure it out
any help would be greatly appreciated

W.t+1/2t(squared)

I have 14*5+1/2*2.8(squared)
70+3.92=73.92

Any help would be greatly appreciated again thanks
 
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Bump, please help me
 
Bump, any clarification that can be done on my part?
 
Wow thanks for the help, your all so great!
 
W.t+1/2t(squared)
Is this supposed to be an equation? Write the whole thing out. Anyway, this equation isn't even correct. You left out a variable. Go back to your textbook and look it up again.

I have 14*5+1/2*2.8(squared)

Even if this was the right equation, you've messed up the calculation. t is not "2.8". Did you try to see if your units worked out properly? If they don't, then that's an indication you are doing something wrong.

Instead of bumping your thread every 20 minutes, try spending the time working on figuring out what's wrong yourself. A careful look at the textbook should have at least made you notice something was wrong with your equation.

Was that helpful enough for you?
 
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