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S. No. Questions Answers

1 What is voltaic cell Voltaic cell is defined as combination of material to

convert the chemical energy into electrical energy. A

voltaic or chemical cell consists of two electrodesmade of different types of metals or metallic

compounds placed in an electrolyte solution.

2 What is battery A Battery is a group of two or more connected Voltaic

cell

3 What is electrode Electrode is a metallic compound or metal which has

abundance of electron (on the negative electrode) and

abundance of positive charges ( on positive electrode).

4 What is Electrolyte Electrolyte is a solution which is capable on conducting a

current in the circuit.

5 What is specific gravity Specific gravity of electrolyte is equal to ratio of weight

of the electrolyte to weight of the equal volume ofwater. Specific gravity of pure electrolyte is 1.835, this

means pure electrolyte is 1.835 times more weighed

weight of water per unit volume. Normally specific

gravity of electrolyte is kept less that 1.35.

6 What is principle of operation of

Hydrometer

A glass float is kept inside of glass tube and glass float

has some weight, while ordinary water is taken inside

glass tube then glass float displaces amount of water

due to its weight, this means due to weight of glass

some volume of water is displaced then specific gravity

of water is indicated on the scale as 1. If any other

electrolyte is there in place of water, it is indicated thatfor same weight How much volume of other electrolyte

shall be displaced which is indicated on the scale made

for water as liquid.

In this case mass of the float is fixed. Specific density of

the electrolyte shall determine How much portion of the

float shall be dipped inside the electrolyte. In my opinion

if specific density is high in comparison with water,

volume of electrolyte displaced shall be less.

Lets us see Archimedes principal

Specific gravity = Specific density of electrolyte/specific

density of water

The operation the hydrometer is based on theArchimedes principle that a solid suspended in afluid will be buoyed up by a force equal to themass of the fluid displaced. Thus, the lower thedensity of the substance, the further thehydrometer will sink.

7 What are the conditions of

shorting of cells

Cells short circuit can be caused by several condition

which included the followings:

http://archimedes.co.tv/http://archimedes.co.tv/http://archimedes.co.tv/

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Faulty separators, lead particles and other particles

forming a circuit between positive cell and negative cell,

buckling of plates, excessive sediments at the bottom of

jars. Primary cause of occurrence of such defects is

overcharging and over discharging of the battery which

causes sediments to build up due to flaking of activematerial and buckling of cell plates.

8 Why gassing occurs in the

battery during charging and

How it can be overcome with

effect of gassing

When Battery voltage reaches at around 2.35V to 2.40V

during the charging of the battery, then further charging

is not directly converted into formation of cell, in this

case Water present in the electrolyte is disassociated bt

electrolysis and Hydrogen is emitted on negative plate

and oxygen is emitted on the positive plate. The

emission of gases is called gassing in the cell/Battery.

One of the way to overcome the gassing to do charging

of cell at reduced rate when cell voltage has reached to

voltage 2.35 or 2.4V/cell