PURPOSE: To demonstrate that a change in the primary current induces a secondary voltage.
DESCRIPTION: The 46-turn primary coil of a transformer is connected through a variable resistor to a 1.5 volt battery, and a large galvenometer is connected directly across the 500-turn secondary, as shown in the circuit diagram below. The primary current in this simple transformer is changed by sliding the variable resistor contact, inducing a secondary potential which is indicated by the galvenometer. Motion of the resistor slider and current in the galvenometer are correlated.
REFERENCES: (PIRA 5K30.20)
EQUIPMENT: Demountable transformer core with coils of 46 turns and 500 turns, 1.5 volt battery, variable resistor, and lecture-demonstration galvenometer.
SETUP TIME: 5 min.
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