3.5 DC Sources of Electricity

Question 1

A zinc-carbon battery life depends upon.
Option A. the amount of zinc.
Option B. the purity of the carbon rod.
Option C. the amount of the electrolyte paste

Answer 1

The amount of zinc

Question 2

When checking the SG of the electrolyte in a lead acid battery, you should.
Option A. check any cell because they will all be the same.
Option B. check only the no. 1 cell because it is the master cell.
Option C. check all cells because they may be different

Answer 2

Check each cell because they may be different

Question 3

The PD at the terminals of an open circuit battery with a small internal resistance will be.
Option A. more than the EMF.
Option B. less than the EMF.
Option C. the same as the EMF

Answer 3

Same as the EMF

Question 4

An accumulation of hydrogen on the plates of a battery is known as.
Option A. polarization.
Option B. ionization.
Option C. hydration

Answer 4

Polarisation

Question 5

What part of a battery is covered in hydrogen during polarization?.
Option A. Anode.
Option B. Both the anode and the cathode.
Option C. Cathode

Answer 5

Anode

Question 6

Which of the following is most likely to cause thermal runaway in a nickel-cadmium battery?.
Option A. A high internal resistance condition.
Option B. High current charging of the battery to more than 100 percent of its capacity.
Option C. Excessive current draw from the battery

Answer 6

High current charging of the battery to more than 100 percent of its capacity

Question 7

Two batteries 12V and 40 Ah each, are in series. What is the total capacity?.
Option A. 12V 80 Ah.
Option B. 24V 40 Ah.
Option C. 24V 80Ah

Answer 7

24v 40ah

Question 8

If a battery has got low internal resistance, then the.
Option A. no load voltage will be the same as on load voltage.
Option B. on load voltage will be greater than no load voltage.
Option C. no load voltage will be greater than on load voltage.

Answer 8

no load voltage will be greater than on load voltage.

Question 9

Conventional current flow inside a battery is from.
Option A. either anode to cathode or cathode to anode, depending on the active elements.
Option B. cathode to anode.
Option C. anode to cathode

Answer 9

Anode to cathode

Question 10

In a voltaic cell, what is the build-up on the cathode called?.
Option A. Hydration.
Option B. Polarization.
Option C. Sulphation.

Answer 10

Sulphation

Question 11

The voltage of a secondary cell is.
Option A. determined by the active materials on the plates.
Option B. determined by the number of plates.
Option C. determined by the area of the plates

Answer 11

Determined by the active material on the plates

Question 12

In a thermocouple, where is voltage measured?.
Option A. At both junctions.
Option B. At the hot junction.
Option C. At the cold junction

Answer 12

At the cold junction

Question 13

The capacity of a battery is measured in.
Option A. volts.
Option B. ampere-hours.
Option C. cubic centimetres

Answer 13

Ampere hours

Question 14

An aircraft battery on charge from the aircraft generators causes.
Option A. battery voltage to increases to nominal voltage and the charge current decreases.
Option B. internal resistance of the battery to decrease in sympathy with the decreasing charging current.
Option C. battery voltage to decrease to zero until it is fully charged

Answer 14

Battery voltage to decrease to zero until it is fully charged