Question

In the case of a hydrometer for lighter liquids, why is the highest value of density marked near the base of its stem?

Answer 1

The main reason for marking the highest density value near the base of the stem in the case of a hydrometer for lighter liquids is discussed below:

1. The stem in the case of a hydrometer for lighter liquids is marked from 1.000 to 0.500, the highest value being at the base of the stem.
2. When the hydrometer for lighter liquids is made to float in some less dense liquid, it will displace more volume of liquid than water, and hence the stem sinks more in less dense liquid.
3. Marking the highest density near the base of the stem and lower density at the top of the stem enables us to take readings very easily.