The most reliable indicator for assessing a lead-acid battery's state of charge is____________?
Show answer Hide answer
Answer: C. specific gravity of electrolyte
Explanation
As a lead-acid battery discharges, sulfuric acid is consumed and the electrolyte specific gravity drops proportionally. During charging, acid is driven back into the solution, causing specific gravity to rise in direct correlation with charge. This predictable chemical relationship makes specific gravity the most accurate and reliable indicator of charge state. Specific gravity is measured using a hydrometer to test the density of the liquid acid electrolyte solution. Terminal voltage can fluctuate due to surface charge effects, making it less reliable than specific gravity readings. Temperature compensation is often applied to hydrometer readings for precise state-of-charge determinations.
Output voltage can be misleading because surface charge or temporary polarization can show false high readings. Temperature of electrolyte affects battery performance but does not directly indicate the remaining electrical charge state. None of the above is incorrect because specific gravity is definitively the most reliable state-of-charge indicator.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
Related questions
Q1. The active components making up a nickel-iron storage battery are___________?
Show answer Hide answer
Answer: D. all of the above
A nickel-iron storage battery utilizes nickel hydroxide as the active substance on its positive plates. It also incorporates powdered iron and its oxides as the active material on its negative plates. Additionally, the s...
Q2. Battery casing containers must resist acid corrosion and are therefore manufactured using___________?
Show answer Hide answer
Answer: D. all above
Battery containers are manufactured from acid-resistant materials such as hard rubber, glass, or specialized plastics.
Q3. Conventional hydrogen cooling technology allows single-unit generator ratings to be increased to___________?
Show answer Hide answer
Answer: C. 200 MW
Hydrogen gas possesses superior thermal conductivity and heat transfer properties compared to standard air cooling. This enhanced cooling capability removes stator and rotor heat much more efficiently from large turbine...
Q4. The typical charging voltage per cell for an alkaline storage battery is__________?
Show answer Hide answer
Answer: C. 1.7 V
Alkaline storage batteries require a higher potential difference to overcome internal resistance during the charging cycle. Chemical polarization and the nature of the potassium hydroxide electrolyte necessitate a chargi...
Q5. The electrical charge required to liberate one gram-equivalent weight of any substance is designated as _________ constant
Show answer Hide answer
Answer: B. Faraday’s
The electrical charge required to liberate one gram-equivalent weight of any substance is designated as Faraday constant. This fundamental physical constant links chemical mass changes directly to electrical charge in el...
Q6. Electrical power for space satellites is supplied through________?
Show answer Hide answer
Answer: A. solar cells
Solar cells convert sunlight directly into electrical energy through the photovoltaic effect without moving parts. This continuous generation capability provides a reliable power source for electronic equipment operating...