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Flashcards in M3.5 Deck (17):
1

What is internal resistance?

The resistance present inside a battery connect to a load

2

What does internal resistance do?

Restricts the movement of current inside any battery

3

What happens to the internal resistance when the battery discharges?

It rises

4

At what percentage will the internal resistance affect the electrical systems?

Over 75% discharged

5

What happens if the terminal isn’t cleaned properly?

It offers additional resistance to current and voltage

6

What is the difference between primary and secondary cells?

You cant recharge primary but can recharge secondary

7

What is an example of a primary cell?

Zinc-carbon battery

8

What are the two types of secondary cells on an aircraft?

Lead acid or nickel cadmium (connected in series)

9

Lead acid cells consist of what percentage split of sulphuric acid and water?

30% of sulphuric acid and 70% water

10

If a lead acid cell has a voltage of 2V when fully charged, what is its final discharge voltage?

1.83V

11

If a nickel cadmium cell has a voltage of 1.2V when fully charged, what is its final discharge voltage?

1V

12

When is the electrolyte level in a nickel cadmium battery at its lowest?

After discharge

13

When must the electrolyte be refilled in a nickel cadmium battery?

When its fully charged

14

What are the advantages of nickel cadmium to lead acid?

-better power to weight ratio
-closed circuit voltage
-larger capacity
(However more costly and larger

15

When batteries are added into a circuit what must be remembered?

They must be the same

16

What happens if a battery is added in series?

The voltage will be added

17

What happens if a battery is added in parallel?

The current of all batteries are added together