# Homework Help: Uncertainity Measurement

1. Dec 7, 2008

### cbrowne

1. The problem statement, all variables and given/known data

I have no idea how to calculate this:

Calculate the uncertainity (limit error) when you convert minutes to hours:

Minutes____Hours__
10.0 0.16
20.0 0.33
30.0 0.5

2. Relevant equations

They've given me like

Time Elapsed in minutes: tm ± 0.1 (min)

Distance Traveled: d ± 0.1 (km)
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

2. Dec 7, 2008

### LowlyPion

What happens when you multiply 60 by the numbers in your table?

What differences do they exhibit relative to the original numbers?

3. Dec 8, 2008

### cbrowne

so should i say the uncertainity is tm ± 0.4 (h) ????

4. Dec 8, 2008

### LowlyPion

Is that what it works out to?

If so ...

5. Dec 8, 2008

### cbrowne

well if u multiply 0.16 x 60= 9.6 but the actual value is 10.0 so its off by 0.4 . As you go up the table the uncertainty becomes smaller and smaller

6. Dec 8, 2008

### LowlyPion

Then ±.4 is the largest absolute error so that would be the greatest uncertainty I'd say.

Expressed as a percentage that would be more like (.4/10) or ± 4%.