REN R110 Lecture 2: Intro math slides
5 Mar 2017
School
Department
Course
Professor
Document Summary
The result should have as many significant digits as the measured number with the smallest number of significant figures. Ex) 123. 45 * 8. 5672 * 56. 321 * 90 = 5360963. 6996676. Pure numbers such as are di(cid:373)e(cid:374)sio(cid:374)less a(cid:374)d are (cid:272)o(cid:374)sidered to ha(cid:448)e a(cid:374) (cid:862)i(cid:374)fi(cid:374)ite(cid:863) a(cid:373)ou(cid:374)t of significant digits. They have no bearing on the # of significant digits. Conversions have dimensions and can have infinite significant digits. Measurements do not gain significant digits by converting to a different unit. Ex) you measure a distance a 1. 2 meters and want to convert it to inches. The measurement does not convert to 47. 2441 inches but to 47 inches. The average of a # of readings must have the same # of significant digits as the readings. Ex) you have 3 readings of 12. 341 lbs, 23. 456 lbs and 34. 567 lbs. A calculator reports the average as 23. 45466667 lbs. Note: the divisor 3 is an exact # and so has an infinite number of decimal places.
