Question

How many significant digits are there when you convert 310 milligrams to micrograms?

Answer 1

is the answer 5? I'm not too sure.

Answer 2

i think it may be 2 or 3...since powers to ten can b neglected...iam also not sure

Answer 3

well in mg we have 0.301. so here the no. of significant digits is 3 right?

Answer 4

i mean 301 mg = 0.301 g

Answer 5

when u convert this into microgram, we get 0.000310 g. do we count the 3 zero's before 3?

Answer 6

oh...we don't count those 3 0's.

Answer 7

got the answer. no. of significant digits in 0.000310g is 3.

Answer 8

but the question is no of s f in micrograms,,u done it in grams

Answer 9

There's no way to know. It depends on whether that final 0 in your "310" is significant. If it is, then 3. if not, then 2. The number of significant digits never depends on the unit in which the measurement is expressed. So whatever sig dig it has in milligrams, it will have in any other unit.

Answer 10

yup...that's right. i just referred a book so i can vouch for my answer as well.

Answer 11

since @auto44 gave us the value as 310mm, i'm assuming that the last 0 is also significant. so i think the answer should be 3.

Answer 12

The significance of trailing zeros in a number not containing a decimal point can be ambiguous. For example, it may not always be clear if a number like 1300 is precise to the nearest unit (and just happens coincidentally to be an exact multiple of a hundred) or if it is only shown to the nearest hundred due to rounding or uncertainty. Various conventions exist to address this issue:
A bar may be placed over the last significant figure; any trailing zeros following this are insignificant. For example, 1300 has three significant figures (and hence indicates that the number is precise to the nearest ten).
The last significant figure of a number may be underlined; for example, "2000" has two significant figures.
A decimal point may be placed after the number; for example "100." indicates specifically that three significant figures are meant.[2]
In the combination of a number and a unit of measurement the ambiguity can be avoided by choosing a suitable unit prefix. For example, the number of significant figures in a mass specified as 1300 g is ambiguous, while in a mass of 13 hg or 1.3 kg it is not.
However, these conventions are not universally used, and it is often necessary to determine from context whether such trailing zeros are intended to be significant. If all else fails, the level of rounding can be specified explicitly. The abbreviation s.f. is sometimes used, for example "20 000 to 2 s.f." or "20 000 (2 sf)". Alternatively, the uncertainty can be stated separately and explicitly, as in 20 000 ± 1%, so that significant-figures rules do not apply. GOT FROM WIKI

Answer 13

gr8! now its clear for me! thanks!

Answer 14

correction in 2000 the bar is over the 0 after 2

Answer 15

and in 1300 the bar is over the last but not least 0