Question: The active material of the positive plates of silver-zinc batteries is_________?

• 1. silver oxide
• 2. lead oxide
• 3. lead
• 4. zinc powder

Question: The average charging voltage for alkali cell is about__________?

• 1. 1 V
• 2. 1.2 V
• 3. 1.7 V
• 4. 2.1 V

Question: The watt-hour efficiency of a lead-acid cell varies between________?

• 1. 25 to 35%
• 2. 40 to 60%
• 3. 70 to 80%
• 4. 90 to 95%

Question: Trickle charging of a storage battery helps to___________?

• 1. maintain proper electrolyte level
• 2. increase its reserve capacity
• 3. prevent sulphation
• 4. keep it fresh and fully charged

Question: It is noticed that durum charging___________?

• 1. there is a rise in voltage
• 2. energy is absorbed by the cell
• 3. specific gravity of H2SO4 is increased
• 4. all of the above

Question: As compared to a lead-acid cell, the efficiency of a nickel-iron cell is less due to its__________?

• 1. compactness
• 2. lower e.m.f.
• 3. small quantity of electrolyte used
• 4. higher internal resistance

Question: In a lead-acid cell dilute sulfuric acid (electrolyte) approximately comprises the following__________?

• 1. one part H2O, three parts H2SO4
• 2. two parts H2O, two parts H2SO4
• 3. three parts H2O, one part H2SO4
• 4. all H2S04

Question: Those substances of the cell which take active part in chemical combination and hence produce electricity during charging or discharging are known as________materials:

• 1. passive
• 2. active
• 3. redundant
• 4. inert

Question: During the charging and discharging of a nickel-iron cell____________?

• 1. corrosive fumes are produced
• 2. water is neither formed nor absorbed
• 3. nickel hydroxide remains unsplit
• 4. its e.m.f. remains constant

Question: A dead storage battery can be revived by___________?

• 1. adding distilled water
• 2. adding so-called battery restorer
• 3. a dose of H2SO4
• 4. none of the above