Calculate the Acceleration of this Car

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The calculation of the car's acceleration was initially deemed correct at 8 m/s², but issues arose when entering the answer into a test. It was suggested that online scoring algorithms may require specific formatting, such as including a space between the numerical value and the unit. The importance of adhering to SI unit conventions was emphasized, as incorrect formatting could lead to misinterpretation of the answer. Clarity in unit representation is crucial to avoid ambiguity, as seen in examples like "8A" which could represent multiple meanings without proper spacing. Proper instruction on formatting is essential for accurate submissions.
dvkdcmfvifmceif123
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Homework Statement
A car starts from rest and accelerates uniformly over a time period of 5 seconds for a distance of 100 meters. What is the acceleration of the car?
Relevant Equations
a = (vf − vi) / Δt
I calculated the average speed (100/5=20) and assumed that the speed at 100 m would be double that (20*2=40), since the speed starts at zero. Then i used the formula for acceleration with time and velocity (a = (vf − vi) / Δt) and got the following answer:
a=(40-0)/5=8 m/s/s. This answer makes sense to me, but when i enter it into the test it says it's wrong.
 
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The test is incorrect or you are somehow managing to enter a format that is not accepted, which would seem strange considering all you probably need to enter is an 8 ...
 
Orodruin said:
The test is incorrect or you are somehow managing to enter a format that is not accepted, which would seem strange considering all you probably need to enter is an 8 ...
Thank you. I just had to make sure
 
Some online scoring algorithms expect units next to numerical answers. Is there a space for units?
 
dvkdcmfvifmceif123 said:
a=(40-0)/5=8 m/s/s. This answer makes sense to me, but when i enter it into the test it says it's wrong.
Worth trying 8m/s^2. Or, if there is a way to enter it, 8m/s2.

Edit. I should of course have writtten "8 m/s^2" and "8 m/s2".
 
Last edited:
kuruman said:
Some online scoring algorithms expect units next to numerical answers. Is there a space for units?
This should of course be specified by the instructions.

It should generally not be encouraged to write without a space between the measured value and the unit.
 
Orodruin said:
This should of course be specified by the instructions.

It should generally not be encouraged to write without a space between the measured value and the unit.
Great advice. Is "8A" 8 amperes, or the hexadecimal value 8A, or 8 times the variable A? If "8A" is allowed to represent 8 Amperes there are three options, when a space is forgotten between number and it's unit

Where "8 A" is crystal clear, 8 Amperes, only has one meaning. Is why space is required.
 

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