Subelement A: — Topic :
Question 6A250
Element 6 (Radiotelegraph)A dry cell may be tested:
Explanation
To accurately assess a dry cell's condition, testing under load is crucial. A failing dry cell often exhibits a normal "no-load" voltage due to its internal resistance not dropping voltage without current flow. However, once a load is applied (even a small one, like a resistor or the device it powers), the internal resistance causes a significant voltage drop, revealing its true depleted state. Therefore, it *must be tested under normal load conditions* to get a realistic reading (A).
Furthermore, the voltage measurement itself can *be taken by any conventional voltmeter* (C). Standard analog or digital voltmeters are designed to measure DC voltage and are perfectly suitable for checking a dry cell's output.
Since both statements A and C are correct, the best answer is D. While you *can* test a dry cell under no load (B), this often provides a misleadingly high voltage reading for a dying battery, making it an unreliable method for determining its practical usefulness.
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