> *Jake marks -10 off on Ross's physics quiz* > For full credit, your answer should be: > > The distance from the Earth to the Sun varies because the Earth's orbit about > the Sun is elliptical.At it's closest, the distance is 91,402,000 miles and > it's farthest distance it is 94,512,000 miles.This gives an average distance > of 92,957,000 miles. Light travels at 186,282 miles per second. Dividing the > average distance by the speed of light gives 499.01225 seconds which is > 8.3168708 minutes.
Yeah, well, I'll take off -10 from you for messing up the significant digits. If you used 92,957,000 (maybe 5, maybe 8 sig figs) divided by 186,282 (5 sig figs) your answer should contain no more than 5 sig figs -- you wrote down 8. Here's the rule: Rule For Expressing Proper Number Of Significant Digits In An Answer From Multiplication or Division For multiplication AND Division there is the following rule for expressing a computed product or quotient with the proper number of significant digits: THE PRODUCT OR QUOTIENT WILL BE REPORTED AS HAVING AS MANY SIGNIFICANT DIGITS AS THE NUMBER INVOLVED IN THE OPERATION WITH THE LEAST NUMBER OF SIGNIFICANT DIGITS. source: http://members.aol.com/profchm/sig_fig.html ____________________ BYU Unix Users Group http://uug.byu.edu/ ___________________________________________________________________ List Info: http://uug.byu.edu/cgi-bin/mailman/listinfo/uug-list
