Question
The mass of a box measured by a grocerís balance is 2.300 kg. Two gold pieces of masses 20.15 g and 20.17 g are added to the box. What is
(a) the total mass of the box,
(b) the difference in the masses of the pieces to correct significant figures ?
Solution
a) The total mass of the box is equal to the sum of the masses of box and constituents in the box.
i.e. M = 2.3 + 0.02015 + 0.02017
= 2.34032 kg
Mass of the box is least accurate to one tenth of kg only. Therefore, the result must not be more accurate than one tenth of kg.
Total mass of the box, M = 2.3 kg
b) Difference in masses of the pieces = 0.02 g
i.e. M = 2.3 + 0.02015 + 0.02017
= 2.34032 kg
Mass of the box is least accurate to one tenth of kg only. Therefore, the result must not be more accurate than one tenth of kg.
Total mass of the box, M = 2.3 kgb) Difference in masses of the pieces = 0.02 g
