Significant Digits • Non-zero digits are always significant • 291 has three significant digits • 29.18 has four significant digits • Zeroes placed before other digits are not significant • 0.095 has two significant digits • Zeroes placed between other digits are always significant • 105 volts has three significant digits.
Significant Digits … • Zeroes placed after other digits but behind a decimal point are significant • 2.500 has four significant digits • Zeroes at the end of a number are significant only if they are behind a decimal point as in previous case • 4900 has two significant digits • 4900. has four significant digits
Significant Digits … • Definitions have infinite significant digits • 100 cm in a meter, 60 minutes in an hour, etc. • Do not write more digits in an answer (intermediate or final) than the fewest digits in the given data • Round-off the answer to appropriate number of digits; however, be careful of the context
Significant Digits … • Use of scientific notation is less ambiguous • 4.900 X 103 has four significant digits, 4.90 X 103 has three significant digits, 4.9 X 103 has two significant digits • Click here for a tutorial