Final answer:
In a high tension magneto system, spark plugs fire during the collapse of the secondary circuit. A step-up transformer increases voltage with more secondary winding turns than primary. The primary winding is connected to the input voltage source, while the secondary provides the transformed output voltage.
Step-by-step explanation:
In a high tension magneto system, the plugs fire on the collapse of the secondary circuit. This occurs as the induced magnetic field in the secondary collapses and a high voltage is induced across the spark plugs, causing them to fire. A transformer works on a similar principle of induction. A step-up transformer increases voltage by having more turns in the secondary winding than in the primary. In the case of the example involving the hydrogen-gas discharge tube, a transformer converts 110 V to 5.0 kV, with a given number of turns in the secondary winding proportionally larger than the number of turns in the primary winding to achieve this voltage increase. The transformer's effective resistance can be found using the power dissipation and the primary voltage. To distinguish between the primary and secondary windings in a transformer, you would note that the primary winding is connected to the input voltage source, while the secondary winding provides the transformed output voltage. For a step-up transformer, the secondary will have more turns. Conversely, a step-down transformer will have fewer turns on the secondary compared to the primary.