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Tuesday, September 14, 2010
Lab 3 Prep #4
This is equal to what you did already in Lab 1 #5.
14 comments:
Anonymous
said...
I'm not sure what the diameter of the ball has to do with the velocity of the ball...
I am using equation 1.7 and I am not getting the right answer. I do not know what I am doing wrong and do not understand what we are suppose to do with the diameter of the ball.
I have difficulty calculating deltaVx as well. Plugging into eq. 1.7 will give: deltavx = sqrt((error of the diameter/the diameter)^2+(deltat/t)^2)= wrong answer! What's wrong?!
Remember that when using equation 1.7 you get the RELATIVE error and not the absolute. Therefore use the equation to change relative error DELTAvx/vx to DELTA vx
Is anyone else having a problem with the 2nd question? It is weird, I got all of them correct besides the DeltaT average. Even my answer for the last part, DeltaVx, is correct and it depends on the DeltaT average. My t(s) are .0184, .0184, and .0183. My t(avg) is .0181 s. So the answer I got for DeltaT average is 1.91e-4 s. What am I doing wrong?
my diameter of the ball is .014 and my t avg is .018. For horizontal v(x) i get .014/.018 and get .777 m. This is coming up incorrect. What am i doing wrong?
14 comments:
I'm not sure what the diameter of the ball has to do with the velocity of the ball...
I am using equation 1.7 and I am not getting the right answer. I do not know what I am doing wrong and do not understand what we are suppose to do with the diameter of the ball.
I have difficulty calculating deltaVx as well. Plugging into eq. 1.7 will give: deltavx = sqrt((error of the diameter/the diameter)^2+(deltat/t)^2)= wrong answer! What's wrong?!
vx = diameter(deff)/t(avg) then continue on with equation 1.7
Remember that when using equation 1.7 you get the RELATIVE error and not the absolute. Therefore use the equation to change relative error DELTAvx/vx to DELTA vx
thanks a lot!!! it was very helpful!
Is anyone else having a problem with the 2nd question? It is weird, I got all of them correct besides the DeltaT average. Even my answer for the last part, DeltaVx, is correct and it depends on the DeltaT average. My t(s) are .0184, .0184, and .0183. My t(avg) is .0181 s. So the answer I got for DeltaT average is 1.91e-4 s. What am I doing wrong?
Disregard the last post. My I made a typo for my t(avg) and that completely through off the calculations, even though it said I was correct.
I still am having trouble figuring out Delta Vx. I am using equation 1.7 but I don't know what I am doing wrong.
What did you mean when you wrote " Deff/t avg"
I don't get what I'm doing wrong im using the equation
deltavx = sqrt((error of the diameter/the diameter)^2+(deltat/t)^2) and then multiply by vx
my diameter is 0.014 +\- .001 I keep on getting .377 as the error??? I think that's wrong
Re 9/19 9:50 pm: read the manual.
Re 9/20 9:10 am: Give your calculation explicitely with all numbers included.
my diameter of the ball is .014 and my t avg is .018. For horizontal v(x) i get .014/.018 and get .777 m. This is coming up incorrect. What am i doing wrong?
Units are m/s NOT m
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