# Reducing uncertainty

1. May 11, 2015

### jack edison

1. The problem statement, all variables and given/known data
How would you reduce uncertainty when measuring the density of a material

2. Relevant equations

3. The attempt at a solution
I'm guessing you have to reduce the uncertainty in the mass and volume of the material

2. May 11, 2015

### phinds

Well, that sure seems like a pretty good guess, since that's what density is calculated from, but HOW do you reduce the uncertainty of either measurement? That's really the question.

3. May 11, 2015

### jack edison

wouldn't you just use a material with greater mass, ,but lower volume, i.e giving a greater measurement for density.
% uncertainty = uncertainty/measurement * 100

so if the measurement is greater, won't the % uncertainty be less

4. May 11, 2015

### phinds

How do you propose that lowering the volume will improve the calculation's uncertainty?

Changing material is cheating. Stick to one problem at a time.

5. May 11, 2015

### jack edison

as we are calculating density, if we have a lower volume, we will have greater density. Greater measurements have less uncertainty.
I have no idea

6. May 11, 2015

### haruspex

Surely you are trying to measure the density of a given substance. If you have a lower volume the mass will be less. The density won't change.
It might help if you explain exactly what method you use for determining the density.