Petroleum jelly is applied to the electrical connections to the lead-acid battery___________?

A. Prevent local heating
B. Prevent short-circuiting
C. Reduce path resistance
D. Prevent corrosion

Which of the following cell has a. reversible chemical reaction ___________?

A. Lead-acid
B. Mercury oxide
C. Carbon-zinc
D. Silver-oxide

When two batteries are connected in parallel, it should be ensured that___________?

A. They have same e.m.f.
B. They have same make
C. They have same ampere-hour capacity
D. They have identical internal resistance

Which of the following has lower specific gravity V__________?

A. Dilute h2s04
B. Concentrated h2so4
C. Water
D. Any of the above

Which of the following battery is used for air-craft _____________?

A. Lead-acid battery
B. Nickel-iron battery
C. Dry cell battery
D. Silver oxide battery

In a battery cover is placed over the element and sealed to the top of the battery container. This is done____________?

A. To reduce evaporation of water from electrolyte
B. To exclude dirt and foreign matter from the electrolyte
C. To discharge both of the above functions
D. To discharge none of the above functions

Hydrogen evolved during charging produces explosive mixture when it is more than___________?

A. 2%
B. 4%
C. 6%
D. 8%

Which of the following primary cells has the highest voltage___________ ?

A. Manganese-alkaline
B. Carbon-zinc
C. Lithium
D. Mercury

For a cell to work, which of the following condition(s) become necessary ___________?

A. Two electrodes of different meta’s should be inserted in the electrolyte, not touching each other
B. Electrolyte must chemically react with one of the electrodes
C. Electrolyte liquid or paste should be conducting
D. All above three conditions are necessary

Charging a sulphated battery at high rate results in___________?

A. Boiling of electrolyte due to gassing
B. Warping of plates
C. Damage to separators, cell caps covers and battery case due to excessive temperature
D. All above