M3

Question 1

Resistance Equaation

Answer 1

V=IxR

Question 2

Thermocouples

Answer 2

2 different materials are connected at 1 end and their junction is then heated and a voltage is generated.

Question 3

Thermocouples use?

Answer 3

To measure exhaust gas temps on an aircraft

Question 4

Internal resistance

Answer 4

A battery’s IR always becomes greater as the battery discharges

Question 5

Terminal Voltage

Answer 5

The voltage you would measure once the device is working

Question 6

Source Voltage

Answer 6

The voltage a source generates before use

Question 7

When are cells connected in a parallel series

Answer 7

If the like terminals are connected.

(Voltage is constant but the current goes up)

Question 8

When are cells connected in series?

Answer 8

When unlike terminals are connected

(The voltage will go up when more cells are added but the current will stay the same)

Question 9

What are the other galvanic cells?

Answer 9

Mercury oxide coin cells
Silver oxide coin cells
Lithium coin cells
Nickel cadmium batteries

Question 10

Advantages of a nickel cadmium battery compared to a lead acid battery

Answer 10

Better power to weight ratio
Closed circuit voltage
Remains almost constant during discharge
Larger capacity

Question 11

When can you refill a nickel cadmium battery

Answer 11

Only when fully charged as the level rises during charging

Question 12

When is the level in nickel cadmium battery’s at its lowest?

Answer 12

After discharge

Question 13

Lead acid battery

Answer 13

Charge value - 2v

Discharge value - 1.83v

Positive plate - lead peroxide

Negative plate - pure spongy lead

Electrolyte - sulphuric acid 30%, water 70%