1Q: What is meant by specific gravity(S.G.)?
Ans: The ratio of the density of a liquid to the density of 4 degree Celsius water is referred as S.G. or specific density.
2Q: How is S.G. measured?
Ans: S.G. is measured by a hydrometer.
3Q: What is hydrometer?
Ans: Hydrometer is an instrument meant for the measurement of S.G. of a solution. It is based on the principle of Archimedes.
4Q: What is meant by AHC?
Ans: The ampere hour capacity of a cell is referred as AHC. It is equal to the product of amperes and the hours for which the cell/battery is capable to work.
5Q: What are the principal defects of a lead-acid battery?
Ans: They are (1) Corrosion (2) Sedimentation (3) Sulphation and (4) Buckling.
6Q: What is corrosion?
Ans: The formation of an insulating layer on the battery terminals is called corrosion. It is a routine defect and it can be reduced by periodically cleaning and greasing the battery terminals.
7Q: What is sedimentation?
Ans: The formation of a pile of sediment at the bottom of a battery is called sedimentation. The defect can be minimised by using distilled water as and when required to be poured in the battery.
8Q: What is sulphation?
Ans: The deposition of a hard layer of lead sulphate on the plates of a battery is called sulphation. A battery should not be left idle in order to avoid this defect.
9Q: What is buckling?
Ans: The bending of cell plates is called buckling. A battery should not be charged or discharged at a high current rate(above 25 A) in order to avoid this defect.
10Q: What is an alkaline cell?
Ans: A cell employing an alkali electrolyte is called an alkaline cell.
11Q: What is Edison cell?
Ans: Edison(or nickel-iron) cell consists of nickel plated steel tubes which are perforated and are filled with a paste of nickel-hydroxide to act as positive plates. The pockets of negative plates are filled with ferrous hydroxide. Caustic-potash and lithium hydroxide mixture is used as an electrolyte.
12Q: What is the e.m.f. of an Edison cell?
Ans: Its e.m.f. is 1.4 volts in charged state and 1.1 volts in discharged state.
13Q: What is a nickel-cadmium cell?
Ans: A nickel-cadmium or Junger cell is an alkaline cell in which active materials are nickel-hydroxide and cadmium.
14Q: What are the merits of alkaline cell over lead-acid cell?
Ans: (1) Alkaline cell can withstand heavy current rate discharging.
(2) It is light in weight and it is mechanically rigid.
(3) It has no sulphation defect.
(4) It is most suitable for electric operated vehicles.
15Q: What is the difference between source and load e.m.f. of a cell/battery?
Ans: The open circuit voltage of a cell/battery is known as source e.m.f. while the voltage across the cell/battery is a closed circuit is known as load voltage or load e.m.f.
16Q: Why cells are joined in parallel?
Ans: Cells are joined in parallel in order to obtain a high current rate or current for more time than that with one cell.
I = n.E/R + n.r
Where, I = Circuit current, amps.
n = Number of cells.
E = E.M.F. of one cell, volts.
R = Load resistance, ohms.
r = Internal resistance of one cell, ohms.
Working from ptc sites is a good time pass as well as we will earn some money.
Visit: www.moneypond.weebly.com
Writing articles is a time pass work.
For some people it is a hobby.
Interesting thing is, this hobby makes you earn good income as well as life time income.
Visit: http://work5minutes2earngoodincome.blogspot.in/
Ans: The ratio of the density of a liquid to the density of 4 degree Celsius water is referred as S.G. or specific density.
2Q: How is S.G. measured?
Ans: S.G. is measured by a hydrometer.
3Q: What is hydrometer?
Ans: Hydrometer is an instrument meant for the measurement of S.G. of a solution. It is based on the principle of Archimedes.
4Q: What is meant by AHC?
Ans: The ampere hour capacity of a cell is referred as AHC. It is equal to the product of amperes and the hours for which the cell/battery is capable to work.
5Q: What are the principal defects of a lead-acid battery?
Ans: They are (1) Corrosion (2) Sedimentation (3) Sulphation and (4) Buckling.
6Q: What is corrosion?
Ans: The formation of an insulating layer on the battery terminals is called corrosion. It is a routine defect and it can be reduced by periodically cleaning and greasing the battery terminals.
7Q: What is sedimentation?
Ans: The formation of a pile of sediment at the bottom of a battery is called sedimentation. The defect can be minimised by using distilled water as and when required to be poured in the battery.
8Q: What is sulphation?
Ans: The deposition of a hard layer of lead sulphate on the plates of a battery is called sulphation. A battery should not be left idle in order to avoid this defect.
9Q: What is buckling?
Ans: The bending of cell plates is called buckling. A battery should not be charged or discharged at a high current rate(above 25 A) in order to avoid this defect.
10Q: What is an alkaline cell?
Ans: A cell employing an alkali electrolyte is called an alkaline cell.
11Q: What is Edison cell?
Ans: Edison(or nickel-iron) cell consists of nickel plated steel tubes which are perforated and are filled with a paste of nickel-hydroxide to act as positive plates. The pockets of negative plates are filled with ferrous hydroxide. Caustic-potash and lithium hydroxide mixture is used as an electrolyte.
12Q: What is the e.m.f. of an Edison cell?
Ans: Its e.m.f. is 1.4 volts in charged state and 1.1 volts in discharged state.
13Q: What is a nickel-cadmium cell?
Ans: A nickel-cadmium or Junger cell is an alkaline cell in which active materials are nickel-hydroxide and cadmium.
14Q: What are the merits of alkaline cell over lead-acid cell?
Ans: (1) Alkaline cell can withstand heavy current rate discharging.
(2) It is light in weight and it is mechanically rigid.
(3) It has no sulphation defect.
(4) It is most suitable for electric operated vehicles.
15Q: What is the difference between source and load e.m.f. of a cell/battery?
Ans: The open circuit voltage of a cell/battery is known as source e.m.f. while the voltage across the cell/battery is a closed circuit is known as load voltage or load e.m.f.
16Q: Why cells are joined in parallel?
Ans: Cells are joined in parallel in order to obtain a high current rate or current for more time than that with one cell.
I = n.E/R + n.r
Where, I = Circuit current, amps.
n = Number of cells.
E = E.M.F. of one cell, volts.
R = Load resistance, ohms.
r = Internal resistance of one cell, ohms.
Working from ptc sites is a good time pass as well as we will earn some money.
Visit: www.moneypond.weebly.com
Writing articles is a time pass work.
For some people it is a hobby.
Interesting thing is, this hobby makes you earn good income as well as life time income.
Visit: http://work5minutes2earngoodincome.blogspot.in/
No comments:
Post a Comment