Physics help-Sources of errors and limitations

[Shordaay]

Physics help---Sources of errors and limitations

Two sources of errors and limitations for Eiffel tower lab to prove that it expands in the summer when it is heated and it contracts in the winter when it cools.
Here is the procedure for the experiment i designed:
1. Attach a fixed stick to the tip of the tower and attach the string to the end of the stick.
2. Attach the rubber band to the other end of the string that ends right at the surface of the ground.
3. Mark a point unto the rubber band about 1 meter from the ground.
4. Measure the Eiffel tower in the winter and record your results.
5. Return in the summer and measure it again. If there is a gap between the rubber band and the ground and the point marked has gone above or below a meter then it is proven that the Eiffel tower has expanded. Record your results.

Two sources of errors for center of gravity of an irregular shaped object lab:


Two sources of errors and limitations for fluid and pressure lab. this lab is to prove that fluid and pressure varies with the size of the opening(hole)


Any help anyone? Please?

 

[CWatters]

Regarding the first part... Your experiment relies on a crucial difference between steel and string but you don't mention it. Why use string and not (for example) a steel wire? Isn't the point of the question to spell out it's limitations and possible sources of error? I can think of several sources of error if you really did use string!

Your attempt at part two for the fluids lab is missing :-)

 

[Shordaay]

What do you mean the part two to the fluid lab is missing? it isnt? and i did use string as i explained in my procedure. yes the point of the question is to find sources of errors and limitations for the labs mentioned. i didnt use steel wire because the teacher didnt recommend that

 

[CWatters]

i didnt use steel wire because the teacher didnt recommend that

Do you understand why a steel rope wasn't recommended? Have a think about it. When you understand why a steel rope wouldn't be a great choice you might see why the choice of material is important and how it can introduce a source of error. Hint: Why would this be a good material to use... http://en.wikipedia.org/wiki/Invar

As for the other labs..

Two sources of errors for center of gravity of an irregular shaped object lab:

Two sources of errors and limitations for fluid and pressure lab. this lab is to prove that fluid and pressure varies with the size of the opening(hole)

Have you already had a go at designing experiments for these two?

 

[Shordaay]

yes i have had a go at designin the lab the only problem i have is thinkin of the sources of errors and limitations and they are due monday and i just can't think of possible sources of errors. No i don't understand why it wasnt recommended. i guess i have to research on that.