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Question
A semiconductor device is connected in series with a battery, an ammeter and a resistor. A current flows in the circuit. If. the polarity of the battery is reversed, the current in the circuit almost becomes zero. The device is a/an ______.
Options
intrinsic semiconductor
p-type semiconductor
n-type semiconductor
p-n junction diode
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Solution
A semiconductor device is connected in series with a battery, an ammeter and a resistor. A current flows in the circuit. If. the polarity of the battery is reversed, the current in the circuit almost becomes zero. The device is a/an p-n junction diode.
Explanation:
When the battery's polarity is reversed, the p-n junction becomes reverse bias. As a result, its resistance rises and the current through the junction falls to nearly zero.
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