Which statement about hydrometer temperature correction is true?

Which statement about hydrometer temperature correction is true?

• A. Temperature corrections are required only for electrolyte temperatures below 59 deg
• B. Temperature corrections are required for all electrolyte temperatures
• C. Temperature corrections are never required
• D. Temperature corrections are only required at temperatures exactly 80 deg

Answer: (A)

Hydrometer readings assume a standard temperature, typically 60°F. Temperature changes affect electrolyte density: cooler temperatures make the electrolyte denser, so the hydrometer floats higher and indicates a higher specific gravity than the true value at the reference temperature. To compare readings accurately, a temperature correction is applied when the electrolyte is cooler than the standard. In many battery testing procedures, this correction is required only when the electrolyte temperature is below about 59°F. If the electrolyte is at or above that temperature, the correction is not applied because the deviation is within the instrument’s tolerance. So, temperature corrections are needed only for electrolyte temperatures below 59°F.

Hydrometer readings assume a standard temperature, typically 60°F. Temperature changes affect electrolyte density: cooler temperatures make the electrolyte denser, so the hydrometer floats higher and indicates a higher specific gravity than the true value at the reference temperature. To compare readings accurately, a temperature correction is applied when the electrolyte is cooler than the standard. In many battery testing procedures, this correction is required only when the electrolyte temperature is below about 59°F. If the electrolyte is at or above that temperature, the correction is not applied because the deviation is within the instrument’s tolerance. So, temperature corrections are needed only for electrolyte temperatures below 59°F.