Question

A torsion balance has a sensitivity requirement (SR) of 4.5 mg. What is the MWQ of this balance if the maximum error permitted in using it is 3.6%?

Answer 1

Step-by-step explanation:

MWQ means the minimum weighable quantity.

Mathematically, MWQ =
`\frac{Sensitivity}{1 - \text{fraction of accuracy}}`

or, MWQ =
`\frac{sensitivity}{\text{fractional error}}`

It is given that sensitivity is 4.5 mg and maximum permitted error is 3.6%.

Therefore, fraction error =
`(3.6)/(100)` = 0.036

Hence, we will calculate MWQ as follows.

MWQ =
`\frac{sensitivity}{\text{fractional error}}`

=
`(4.5 mg)/(0.036)`

= 125 mg

Thus, we can conclude that the MWQ of the given balance is 125 mg.