P. 4086. A black box has two leads. If a zero-centre ammeter and a rechargeable battery of 6 V voltage, whose internal resistance is negligible, are connected to the leads as shown in the figure, the ammeter reads 1 A. If the terminals of the battery are swapped, and connected again into he circuit, then the measured current is 0.5 A.
What is in the box?
Deadline expired on 13 October 2008.