Hydrometer FAQs:

Q: Is a hydrometer an instrument that measures the specific gravity of liquids—the ratio of the density of the liquid to the density of water?

A: Yes.

Q: Are hydrometers testing the quality of the antifreeze solution used for engine cooling?

A: Yes.

Q: Are hydrometers calibrated for different uses?

A: Yes, and such as a lactometer for measuring the density of milk, a saccharometer for measuring the density of sugar in a liquid, or an alcoholometer for measuring higher levels of alcohol in spirits.

Q: Is a hydrometer usually made of glass?

A: Yes, and consists of a cylindrical stem and a bulb weighted with mercury or lead shot to make it float upright.

Q: Is a hydrometer based on Archimedes' principle that a solid suspended in a fluid is buoyed by a force equal to the weight of the fluid displaced by the submerged part of the suspended solid?

A: Yes.

Q: Are hydrometers used — covering specific gravity ranges of 1.0–0.95?

A: Yes, and 0.95–0.9 etc.

Q: Is a hydrometer a hydrometer that has a thermometer enclosed in the float section?

A: Yes.

Q: Is a hydrometer gently lowered into the liquid until it floats freely?

A: Yes.

Q: Are hydrometers frequently named for their use: a lactometer?

A: Yes, and for example, is a hydrometer designed especially for use with dairy products.