(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Hey there, I need some help with uncertainties and how to find the speed of a moving object. I have tried to solve the problem several times but my answer seems to be wrong.

Formula for speed : v=d/t

My uncertainties: 0.5cm (distance) and 0.5s for time. The uncertainties were measured with the same analog.

I did the experiment 15 times and got different speed result of the object each time. The total sum of the speeds ( 15 trials) was 44.99s. The average of that is 2.99 (15/44.99)

Oh and my measuring device was 228cm long (exact)

I need to find out the speed and the uncertainties

If I missed any detail please please let me know

PLEASE HELP!!! I'am very frustrated right now..=S

2. Relevant equations

Formula to use : v=d/t

3. The attempt at a solution

v=d/t

= (228 +\- 0.5)m/(2.99+\- 0.5)s

228 divided by 0.5 = 456%

2.99 divided by 0.5= 5.78%

456% +5.78%=461.98%

so now 461.98% * 76.2 ( which I got by diving 288 and 2.99)

my final answer was v=76.25m? +\- 39%..

I'am confused..

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# Homework Help: Easy uncertainty question, I need HELP

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