Uniform Acceleration problem dealing with time and x variables?

AI Thread Summary
An object with an initial velocity of 14.0 cm/s moves with uniform acceleration, starting at an x-coordinate of 3.00 cm. After 2.00 seconds, its x-coordinate changes to -5.00 cm, prompting a calculation for acceleration using the equation deltaX = V naught t + (1/2)at^2. The user initially miscalculated by incorrectly substituting values into the formula, leading to an incorrect acceleration result. After clarification, the correct substitution revealed the mistake, highlighting the importance of careful variable management in physics problems.
OUmecheng
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Homework Statement


An object moving with uniform acceleration has a velocity of 14.0 cm/s in the positive x direction when its x coordinate is 3.00 cm. If its x coordinate 2.00 s later is -5.00 cm, what is its acceleration?

Homework Equations


deltaX=V naught t + (1/2)at^2)

The Attempt at a Solution


2(X-Vt)/t^2 = a

I rewrote the equation and plugged in the variables... Didn't seem to get the right answer. I'm all out of ideas... I really don't know where to go from there... I've spent 30mins on this problem so far.
 
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Your formula is correct. What answer did you get? If you show the details of the substitution it should be easy to pinpoint the error (if there is one).
 
= 2((-5.00 cm-3.00 cm) - (14.0 cm/s)(2.00 s)) / (14.0 cm/s)^2

= 2(-8 cm - 28 cm) / 196 cm^2/s^2

= -0.367 cm/s^2NOT the correct answer.
 
= 2((-5.00 cm-3.00 cm) - (14.0 cm/s)(2.00 s)) / (14.0 cm/s)^2
In place of your 14.0, I had 2. The time is 2, not 14.
 
Delphi51 said:
In place of your 14.0, I had 2. The time is 2, not 14.

ahhhhhh thank you!

I am brilliant haha.
 
Everyone has made their share of little mistakes!
 
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