Solving Basic Physics Problem: Help with x=8.0m/s*5.0s+ .5*3.0m/s^2*(5.0s)^2

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The discussion centers on solving the physics equation x = 8.0 m/s * 5.0 s + 0.5 * 3.0 m/s² * (5.0 s)². The user calculates the first term correctly as 40 but fails to square the time in the second term, leading to an incorrect total of 47.5 instead of the expected 77.5. Clarification is provided that the time must be squared when calculating the second term, which is crucial for obtaining the correct answer. The importance of proper algebraic manipulation in physics problems is emphasized. Understanding the squaring of time is essential for accurate calculations in kinematics.
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Hi I am studying for this first physics test and having trouble.

heres the equation I am using to find x and I am sure its right but i can't seem to get the answer they do

x=8.0m/s*5.0s +.5 * 3.0m/s^2 * (5.0s)^2 = 77.5

I am not getting the 77.5

8 *5 = 40

3.0 x 5.0 = 15

15 * .5 = 7.5

so 40 + 7.5 = 47.5

I have a feeling that it has something to do with the time being squared buy my algebra sucks.. can someone explain this solution.
 
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the equation is x=\frac{1}{2}at^2+v_ot you forgot to square the time when multiplying against acceleration
 
What is the question? what is the problem with things you have done? Pls be specific.
 
mrserv0n said:
Hi I am studying for this first physics test and having trouble.

heres the equation I am using to find x and I am sure its right but i can't seem to get the answer they do

x=8.0m/s*5.0s +.5 * 3.0m/s^2 * (5.0s)^2 = 77.5

I am not getting the 77.5

8 *5 = 40

3.0 x 5.0 = 15

15 * .5 = 7.5

so 40 + 7.5 = 47.5

I have a feeling that it has something to do with the time being squared buy my algebra sucks.. can someone explain this solution.

x=8.0m/s*5.0s +.5 * 3.0m/s^2 * (5.0s)^2 = 77.5

Yes, it is "the time being squared"- you didn't square! What is 52?
 
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