Solve Mechanics Question: Find Acceleration, Final Speed, & Average Speed

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The discussion revolves around solving a mechanics problem involving a ball rolling down a ramp. The user seeks feedback on their calculations for acceleration, final speed, and average speed. They initially propose using the formula a = s/t^2 for acceleration and express confusion about calculating final speed. The conversation clarifies that average speed can be determined as total displacement over total time, and both methods yield the same result if acceleration is constant. The user ultimately acknowledges the correct approach to finding average speed.
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This was one of my homework assignments...
I wanted to know if my steps taken are correct.
Thanks for any feedback.

A ball rols down a ramp and travels a distance of 3.00 m in 2.05 seconds. Find (a) what is the ball's acceleration? (b) what is the ball's final speed at the bottom of the ramp? And (c) what is the ball's average speed going down the ramp?
(a) I thought I'd use the formula a = s/t^2 where s = distance, 3m, and t = time, 2.05s.
(b) I thought I'd multiply what I've gotten for acceleration by 2.05s... or is this a conceptual thing where it's assumably 0? I don't know...
(c) Average speed I'm guessing is the same as (b).
 
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s = (1/2)at^2 not at^2


average speed is (u + V)/2
 
mukundpa said:
s = (1/2)at^2 not at^2


average speed is (u + V)/2
Oh, OK...
I get the 0.5at^2 part, but isn't average speed total displacement over total time rather than the arithmetic mean of the 2 velocities? :\
 
yes, if the acceleration is constant both will give the same result.
 
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