Choose the correct option for the following battery assertion & reason questions.
- Both A and R are true and R is a correct explanation of A
- Both A and R are true but R is not a correct explanation of A
- A is true but R is false
- A is false but R is true
Q. (A): During charging of a lead-acid cell the electrolyte becomes stronger.
(R): During charging sulphuric acid is formed.
Q. (A): Lead-acid battery container is made up of glass, lead-lined wood, ebonite, hard rubber of bituminous compound ceramic materials or moulded plastics.
(R): Containers of lead-acid batteries should be acid-resistant.
Q. (A): For preparing electrolyte for a lead-acid battery, acid is poured into water (water is never poured into the acid).
(R): Pouring of water into the acid while preparing electrolyte for the lead-acid battery will result in an explosion.
Q. (A): In a lead-acid battery, the level of electrolyte must be maintained at least 10 or 15 mm above the plates.
(R): If the plates of a lead-acid battery are exposed to air, its capacity and life will reduce and exposed portion of plates will be converted into lead sulphate.
Q. (A): Nickel-cadmium accumulators are superior to nickel-iron accumulators.
(R): Nickel-cadmium accumulators have higher voltage per cell, less weight and low cost in comparison to those of nickel-iron accumulators.
Q. (A): Nickel iron accumulators are particularly suitable for severe services such as propulsion of industrial trucks and mine locomotives.
(R): Nickel iron accumulators have low running cost and need very less maintenance.
Q. (A): Nickel-iron cell, in comparison to a lead-acid cell, has higher efficiency.
(R): Nickel iron cell has low emf.