Simple Significant Figures Question?

Question

For my physics lab, we must use sig figs....I need to find circumference, so I put:
Calculating the Circumference of Revolution: C=2πR So, C=2π(.60m)=3.8m

Is that right or should it technically be to one place since I multiplied by the 2...or maybe should I put it 2.0?

Answer 1

I've always assumed that the 2 was 2.00000000000000000....etc.

So, I would say use two sig figs.

Answer 2

Two sig figs would be correct because you don't worry about the sig figs from the 2. Because the 2 from the formula is an absolute value (infinite sig figs) your answer would have sig figs according to the experimental or given data.

To eliminate doubt, use the formula C=Dπ where D=diameter becuase the diamer=2R. That way you only have the sig figs from the data to worry about.

Answer 3

I'd have to say it 2 sig figs because the 2 is a constant value and doesn't count towards the final amount of sig figs, in the chem tech program they are sig fig nazis

Answer 4

Well I dont know how your syllabus teaches you(Mine is CBSE).
This is how it goes.Since 2 is a non zero digit it has 1 significant figure.As for 0.6 it has 2 significant figures.We have to go for the lowest significant figures.Therefore:
2pi*0.6=3.77=4

Well im not exactly sure myself.But thats how I do it.