A student measures the diameter of a test tube usin a ruler calibated in cm with graduations marked at each mm. which of the followin reported values is consistent with the markings on teh ruler and the rule of thumb for measuring devices?
A) 1.7 cm
B) 1.74 cm
C) 1.738
2007-01-02 12:34:34 · 4 answers · asked by Anonymous in Science & Mathematics ➔ Chemistry
A) is correct. The others are fantasies of the reporters as the ruler is accurate only to the smallest gradation. Even that is subject to error. And, of course, it needs calibrated as recommended by the manufacturer.
Yeah, ok, but A) is still the only correctly reportable answer. If the reader's eye feels it sees 1.74cm, then the report should be 1.7cm. If it feels it sees 1.78 cm, then the report should be 1.8cm.
2007-01-02 12:50:22 · answer #1 · answered by roynburton 5 · 0⤊ 0⤋
The answer is A) because your accuracy is that of a single graduation mark on either side of what you measure. Certainly you can guesstimate [sic] another digit, as in B) but that is not within the error limit of one graduation. And C) could not be the answer in any sense.
2007-01-02 12:40:38 · answer #2 · answered by kellenraid 6 · 0⤊ 0⤋
A) You can't record measurements smaller than what your measuring device shows. In this case the smallest measurement is the millimeter, hence 1.7.
2007-01-02 12:41:26 · answer #3 · answered by Leif 1 · 0⤊ 0⤋
B is the answer, You read to the nearest mm and you can estimate the next digit.
2007-01-02 12:41:07 · answer #4 · answered by science teacher 7 · 0⤊ 0⤋