Significant figures Definition and 153 Threads

Hi, I am currently taking a college-level Physics course and ran into some troubling questions regarding significant figures. I wasn’t sure which forum I should post this to but the math forum seemed like the most adequate one. So here goes… I have no problem understanding the basic rules for...

When certain quantities are measured, the measured values are known only to within limits of the experimental uncertainty! It's here where significant figures comes on scene. Let us assume that the accuracy to which we can measure the length is +-0.1 cm. If we measured it to be 16.2 cm...

Why do we use significant figures in calculations instead of the rate of Uncertainty? (2,5\pm0,4000)*4,000=(10\pm1,6). The number 2,5 has 2 significant figures, which is the same as we will write in the answer, while it should be only one significant figure in the answer if we take the rate of...

Homework Statement A rocket traveling at 88 m/s is accelerated uniformly to 132 m/s over a 15.0 second interval. What is its average velocity, with the correct number of significant figures? An object traveling at 11.5 m/s is decelerated uniformly to 4.5 m/s. What is its average velocity...

Homework Statement Calculate the speed of the runner. Times, measured to nearest 5 seconds: 95, 100, 85, 80 seconds. Mean Time: 90 seconds. Distance: 200mHomework Equations Speed = Distance/TimeThe Attempt at a Solution Speed = Distance/Time = 200/90 = 2.2222222222 ms-1 Not sure how many...

I'm in Chemistry Honors. Could anyone explain what significant figures are to me, and how you determine the amount of significant figures? [This is not for homework.] Thank you.

Homework Statement The length of a cylinder is 1.2 x 10^-2 m and its radius is 2.12 x 10^-2 m. What is its volume according to significicant figures? Homework Equations The Attempt at a Solution V=(pi)r^2 l r^2 = 4.49 x 10^-4 (as radius has 3 significant digits) V= 22/7 x 4.49...

Hi. Sorry that I abandoned the provided template, but it didn't really apply to the questions that I had..these all deal with significant figures: 1. For the number 100, I understand that there can be one, two, or three significant figures. If there are three, then I understand that the...

I have a question regarding significant figures. I understand the notion well, but am having trouble putting it into practice. My main question is: let's say you divide two numbers of 3 sf each. The result from the calculator is long so you round it to 3 sf. If you need to re-use that result in...

Hi everyone. Hopefully this is easy to solve. I have large amounts of mined data that have differing levels of precision. I want to do analysis of: 1) number of decimal places present 2) significant figure error intervals based on the precision (for instance, 0.003 could have been...

Homework Statement What's the magnitude of A, when A = 4i+4j ? Homework Equations The Attempt at a Solution The answer is sqrt(32), but do Sig Figs matter for this type of problem? Should I write it as 5.66? Or do I leave it as sqrt(32). P.S. - I know in a Math class I would...

Homework Statement 1) How long a piece of wire would you need to form a circular arc subtending an angle of 1.6 rad, if the radius of the arc is 8.1 cm? Express your answer using two significant figures. 2) In 2004 Mizuki Noguchi of Japan won the Women's Olympic Marathon, completing...

What do physicists agree on the number of significant figures to use? I've done some research and I found that the answer has the same number of significant figures as the least precise value used to calculate it. ex: V=IR [I=1.25474] [R=5.2] Hence, voltage is simply 6.5? Thanks...

Homework Statement A newspaper reported an attendance of 15,000. If you assume that this number contains two significant figures, how many people could actually have been at the game? The Attempt at a Solution I'm having difficulty answering this problem not because I don't know how to...

Homework Statement This topic is causing me some slight confusion and I have a few questions I would like to get resolved. When you have a number say like: 0.0800, I would assume that it is 3 sig figs...right? Now say I were to divide it by oh..I don't know..517 (which is also 3 sig...

12.5 100.00 105 2.5 x 10^3 All of these numbers have 3 significant figures right?

A professor sets a 34 hour take-home exam and states: "Please note the Monday, 9 AM deadline". A student hands the paper in at 9:12 AM on Monday. Has the student missed the deadline? Explain. AM

Homework Statement (5.25 * 104) / (100 + 10.5) Homework Equations Significant Figures Rule The Attempt at a Solution The answer in the book states 500 (which has 1 or 2 significant figures). In my first step, I did the addition first in the denominator (100 + 10.5). Adhering to...

Homework Statement How many significant figures in each?: -214 -81.60 -7.03 -.03 -0.0086 -3236 -8700 I don't quite understand this (I'm self studying, need a little help :) ) If got them all right then can someone explain the concept of significant figures? I hate knowing only...

Hey fellows I have read a number of books on Significant figures but I am not able to understand what are these. One confusing thing is that eg. If I take length of wire with a meter rod (with 1 meter minimum length measureable) & found it to be 7 meters. Then according to rule of Significant...

I'm a little confused on how to answer Physics questions in correct decimal places. In Math, I'm used to just giving a couple decimal places and that's fine. In Physics, you do all this rounding over and over and by the end you can be off by many whole numbers. For instance, I took a simple...

Dear forum members, forgive me if the post is out of place, but I am really lost with this subject. I am told that when writing my lab reports I should report the measurements to the same number of significant figures and decimal places, and sometimes I find these two things...

Homework Statement I just wanted to know if I wrote the answer with the correct number of significant figures for this addition problem. 0.00015 M + 0.00004 M + 0.00011 M = 0.00030 M (Correct?) Homework Equations See above. 0.00015 M + 0.00004 M + 0.00011 M = ? The...

EDIT: I finished the assignment other than the two problems listed here, I got 91.66/100 but would love those last 8.44 points, I'll be checking in on this topic Thursday afternoon and might have figured it out by then but I am wary to waste my last attempt. So.. that's the update Ok...

Homework Statement Average acceleration: - The instantaneous velocity at any time can be calculated with the given formula: v = 60 m/s + (0.50 m/s^3) t^2 - Find the instantaneous acceleration at t=1.0s, by taking (delta)t to be 0.1s, then 0.01s, and then 0.001s. Homework Equations a = (delta)v...

Hi just a quick question about sig figs. If one was too divide a time such as 21.76s into increments of twenty to find the period of revolution for a centripetal force experiment would the answer be two or four significant figures? also if I multiply a mass such as 2567kg by acceleration due to...

Homework Statement how many significant figures are there if a scientific notation is added or multiplied to a whole number, let's say 1.) 208998 + 4.7 x 10^5 =?? 2.) (0.0000328) (45.9 x 10^8) =?? Homework Equations The Attempt at a Solution I've been thinking since last...

Let's say I want to round the number 3.549 off to two significant figures. Do I have to round the 4 to 5 first, or do I just round the 5 (in the one-tenths place) to 5, since the one-hundreths digit is 4? If I do it by the first method, it would be 3.6, while the 2nd method gives 3.5. Which is...

I'm sorry if this doesn't fit the proper format for this section of the forum but it seems like the best place to ask this to me. I know all the basic rules of significant figures, however I'm just curious about how it should be applied in equations. For example say I was trying to solve...

Hi everyone, Can someone please help me with this problem? The problem says: A parking lot is 115 ft by 200 ft. Find the area in m2 My attempt: 1m=3.281 ft So (115 ft)(1m/3.281ft)=35.1m (200ft)(1m/3.281ft)=70.0m A=(35.1m)(70.0m) A=2457m2=2.46X10^3m^2 Thank you very much

This isn't really a homework question. It's a question about a book I'm reading out of curiosity, but this seemed to be the most appropriate place to put it. Also, it's not exactly a physics problem, but I did come across this issue while reading a physics related book. I apologize if this...

Should you apply the rules of significant figures when you are doing any kind of physics, chemistry, or mathematics computation? Like, for example if you are doing homework problems in your textbook, should you still follow the sig fig rules or should you only apply them in labs and measurements?

When i have a conversion fact such as, 6.45 mol H_{2\left(g\right)}\times\frac{2 mol HBr_{\left(g\right)}}{2 mol H_{2\left(g\right)} }= 12.9 mol HBr_{g} how many significant figure should the answer have?, I am thinking one.

I am taking measurements off the screen of an analog oscilloscope in order to calculate voltage and frequency of a sinusoidal wave form. The volts per division is set to 0.50V, and the time per division is set to 0.50 ms. I measure the vertical length of the trace to be 2.67 divisions. I...

I have a question about applying the rules of significant figures to calculations. Should one apply the rules to everyday calculations? I don't know if it will benefit me in the long run to count the number of sig/decimal places in numbers in the simplest calculations. If I major in...

Homework Statement This is probably a ridiculous question for many of you, but I want to make sure I have understood the significant figures rule. I am putting this in the physics section because it's from my physics book. The Attempt at a Solution a) Seconds in 1.00 year: 1 year x 365...

The author of my physics book seems to be a little significant-figure-happy: m=150.0, k=225, A=.15, t=3.00, δ=[SIZE="4"][FONT="Times New Roman"]π He does this : -A√k/m)sin(t√k/m)+δ)=-.15*1.22sin(3.00*1.22+[SIZE="4"][FONT="Times New Roman"]π)=-.0907 Whereas I do...

The question is 0.5 x 234.987 And no the answer is not 117.4935 i need to convert that number 117.4935 into one number. As 0.5 is only one significant figure.

If I measured something to be 43.49 centimeters with a meter stick and I wanted to convert that into meters, would it become 0.4349 cm or 0.43 cm?? Thanks

Hello I have 2 questions about sig figs that have been bothering me. I worked out this calculation: (3.652 x 108) (42.8 x 10-6) My answer was 67524.0192. I figured that since there is a 6 in the second parenthesis my answer should be only 1 sig fig. So I expressed it as 7 x 10^4 Can...

I had no clue where to put this, and since this is very elementary and was covered during the beginning of my physics class, I chose here. I basically have some problems accepting some of the significant figure rules. One problem which makes no sense: If say 202 is divided by 356...

Significant Figures and scientific notation! how come 8.231x10^3 - 5.25x10^2 = 7.706*10^2 ? and how come 350 - 10.5 = 3.40x10^2

Hello, I'm new here and thought that maybe I can learn a thing or two from this website. Anyways, I need some help in the subject of Significant Figures. I'm getting confused with some of the rules. Here are the questions that I'm confused with. Subtract and express to the correct...

How many significant figures should be retained in the result of the following calculation. (11.13 - 2.6) * 10^4 ----------------------- (103.05 + 16.9) * 10^-6 is it 1 , 2 , 3 , 4 or 5 ?

How many significant figures should be retained in the result of the following calculation. (11.13 - 2.6) * 10^4 ----------------------- (103.05 + 16.9) * 10^-6 is it 1, 2, 3, 4, or 5 ?

Unit Conversion & Significant Figures Greetings! I would just like to re-check my work: 1) What will be the mass in tons added to a car when its radiator is filled with antifreeze (d = 1.12 g/mL) if the radiator has a capacityof 3.99 gal? Since density = mass/volume, mass =...

I don't really get the concept of significant figures. Anyone can help me out? 1200 X 23.4 What is that in significant figures?

significant figures help needed badly! hows everyone doing in this fine evening? :biggrin: ok i just had some questions on "sig figs" as the pros call it (unfortunately that's not me :frown: :cry: ) ok, i'll try to explain as clearly as i can here: in this manual i have that explains...

o:) ok... So We got 2 number (i) 34500000000 & (ii) 30.4 <both to 3 sig fig> is zero considered a significant figure in this case...? If it is, then why do we include the zeros in 34500000000, if it is not, why, 30.4 and not 30.44?

11. [Walker2 9.P.010.] A 0.50 kg croquet ball is initially at rest on the grass. When the ball is struck by a mallet, the average force exerted on it is 235 N. If the ball's speed after being struck is 2.6 m/s, how long was the mallet in contact with the ball? (in miliseconds) F = ma 235 =...