Question

Please explain how and why the highlighted answers are correct and or steps to solve.

Answer 1

A scale measures the following weight of a light object

`11.000\pm0.034\; lb`

Here 0.034 is the uncertainty in the measurement.

It is given that the percent uncertainty of the scale remains constant.

So, the percent uncertainty of the scale is

`(0.034)/(11.000)*100=0.309\%`

Now, we can use this percent uncertainty of the scale to find the uncertainty for the measurement of 78.000 lb

`(0.309)/(100)*78.000=0.240\; lb`

Therefore, the uncertainty for measurement of 78.000 lb is 0.240 lb