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glamorousbride
Sep 7, 2006, 07:03 PM
(1) A rectangular block of wood is measured to have the dimensions 11.2 cm x 3.4 cm x 4.10 cm. Compute the volume of the block, showing explicitly (by underlining) how doubtful figures are carried through the calculation, and report the final answer with the correct number of significant figures.

Computed volume _________ (im powers-of-10 notation)


(2) in an experiment to determine the value of pie, a cylinder is measured to have an avg. of 4.25 cm for its diameter and an average of 13.39 cm for its circumference. What is the experimental value of pie to the correct number of significant figures?

3) expressing experimental error- if the accepted value of pie is 3.1416, what are the fractional error and the percent error of the experimental value found in (2).


4) in an experiment to measure the acceleration (g) due to gravity, 2 values, 9.96 m/s squared and 9.72 m/s squared are determined. Find: (1) the % difference of the two measurements, (2) the percent error of each measurement and (3) the % error of their mean. (accepted value: g=9.80 m/s squared).




This is where I am now. I am so lost. Please give me some direction. This is for a lab class, and like I said I should not be in the class. I'm not looking for a freebie, we just never learned this in the class. I registered late for the course, and have to hand this in asap separately.

rudi_in
Sep 7, 2006, 07:37 PM
Well, here are some hints you can use on these problems...

1. Rules for significant digits when multiplying

The answer may only have as many significant digits as the value with the least number of significant digits in the problem.

2. Choose an appropriate formula and plug in the information given. Treat pi as the variable and solve for pi.

3. % error is the ((experimental value - accepted value) ÷ accepted value) x 100

4. mean is the same as average