# Uncertainty of measurements & significant figures

ELLE_AW

## Homework Statement

This conversion factor 1m = 39.3701 inches was used, when measuring a tape that had inches on it to a full meter. The measuring tape increased by 0.0625 inch increments, so the 1 meter (39.3701) was estimated to be in between the 39.3125 and 39.3750 on the actual measuring tape.
Based on this what is uncertainty of my measurement in meters? What is the last certain digit? What sig figs would would the meters be reported to accurately (e.g. 1.0 or 1.00) ?

## Homework Equations

conversion factor: 1 m = 39.3701 inches

## The Attempt at a Solution

I think the meter should be written as 1.00

I think the uncertainty would be 0.0625 inches x 1 m / 39.3701 inches = 0.00158 meters

I feel like I"m wrong though.

Homework Helper
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when measuring a tape that had inches on it to a full meter.
Not quite sure what this means.
Is the idea that we are trying to measure off a distance of one metre using this tape? If so, we have to choose which of the ##\frac 1{16}##" marks to use.

ELLE_AW
Not quite sure what this means.
Is the idea that we are trying to measure off a distance of one metre using this tape? If so, we have to choose which of the ##\frac 1{16}##" marks to use.

Figured it out.

Yes, measuring a distance of 1 meter using this tape that has units of inches. Yes, I just wanted to calculate the uncertainty, but it's basically the smallest increment by which the measuring tool (tape in this case) increases... so +/- 0.0625 inches.