Question

CHEMISTRY:
How many significant figures does the number 520 have?

What is the difference between a systematic error and a random error?

Answer 1

520 = 2 sig figs; 520.0 = 4 sig figs.

systematic error: Are predictable, usually can be eliminated if the cause of these errors is found. Caused by imperfect calibration of measurement instruments or imperfect methods of observation.

random error: Always present in measures, and are caused by unpredictable and uncontrollable fluctuations in the reading of the measurement apparatus or in the experimenter's interpretation.

Answer 2

520 has two significant digits.

Systematic Errors are errors that occur from incorrect calibrations on measuring devices, etc.

Random errors are uncontrollable differences in measurement readings that cannot be avoided. Therefore, we always attach a level of uncertainty to our measurements.