I/GCSE Physics Question Analysis Topic: Physics - Short Questions
1) Why is it experimentally difficult to detect neutrinos in nuclear β-decay?
2) Explain, with the help of a circuit diagram, the working of a p-n junction diode as a half-wave rectifier.
1) Because they have essentially no mass and no charge, neutrinos do not readily interact with any matter - making them difficult to detect experimentally in β decay.
2) A p-n junction diode conducts current when in forward bias and blocks it in reverse bias.
In a positive cycle, a p-n junction diode is forward biased. When a diode is such, its resistance, R D, is zero or it shorts out, resulting in an input voltage that is equal to its output voltage.
In the negative cycle, the p-n junction diode is reverse biased. Reverse bias causes the output voltage of the diode to be zero and the diode's resistance, R D, to be equal to infinity.
As a result, only positive cycles are permitted to pass through the p-n junction.
End of analysis. Great!