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A lot of students asked this questions today: you guys have to use the equations posted in lab 1 [eq. 1.8 is the important one here].
The expression for [DeltaT^2] = 2*(DeltaT/T)*T^2 which is not the same as [DeltaT^2] = 2*(DeltaT^2/T^2)*T^2
The 1st expression is correct and will lead to the correct numerical calculation for the last part, but the second expression is not correct. This is so because we do know what DeltaT^2 is, we are trying to find it.
However, Maple will accept both answers for the expressions.
But to find the numerical value you have to use the 1st equation because DeltaT is given to us.
Sorry typo in the last comment, I wrote, "we do know DeltaT^2," but I meant to say, "we DO NOT Know DeltaT^2," thus have to use the 1st equation written.
How do we know when to round off for the error calculations? It seems as if the answers given round off arbitrarily. I thought we were only supposed to give one digit of error?
8 comments:
A lot of students asked this questions today: you guys have to use the equations posted in lab 1 [eq. 1.8 is the important one here].
The expression for
[DeltaT^2] = 2*(DeltaT/T)*T^2
which is not the same as
[DeltaT^2] = 2*(DeltaT^2/T^2)*T^2
The 1st expression is correct and will lead to the correct numerical calculation for the last part, but the second expression is not correct. This is so because we do know what DeltaT^2 is, we are trying to find it.
However, Maple will accept both answers for the expressions.
But to find the numerical value you have to use the 1st equation because DeltaT is given to us.
Goodluck
Sorry typo in the last comment, I wrote, "we do know DeltaT^2," but I meant to say, "we DO NOT Know DeltaT^2," thus have to use the 1st equation written.
How do we know when to round off for the error calculations? It seems as if the answers given round off arbitrarily. I thought we were only supposed to give one digit of error?
I'm a bit confused.
My numbers are 1.58s plus or minus .033s.
To calculate DeltaT^2 I plugged the following numbers into the formula to get:
DeltaT^2 = 2*(.033s/1.58s)(2.496s^2)
where 2.496s^2 = T^2
Am I doing something wrong in this calculation?
If you T=1.58 then shouldn't your T^2=2.496.
Because when you put 2.496^2 that's the same as saying 1.58^4.
How do i get t^2(first part)? im at a complete loss. thank you for any help.
Re 9.9 1:45 am:
Use 3 significant digits . Then you safely within the accuracy requirements of these quizzes.
Im still really lost. I cant seem to find any references on how to get T^2.
I read the Lab and also the graph.
According to the Graph:
if T=0.62s, then T^2=(0.62^2)=0.38
On my Question 7:
T=0.65s, yet if I do 0.65^2, it doesn't work.
Can you guys give me any hints?
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