When a conducting wire is connected between the two electrodes, electrodes move along the wire from the zinc to the carbon, producing an electrical current. After a time, the zinc becomes used up, and the cell must be safely discarded. Some cells can be recharged. Whatever they look like or their function, all cells contain electrodes and an electrolyte. The other is the separation of these metals by a compound that doesn't carry an electrical current.
All batteries have many characteristics in common.
When an electrical wire is attached across the two electrodes, electrons transfer through the wire from the zinc to the carbon, generating heat. After a while, the zinc becomes used up, and the battery must be recharged. This test, like the SVT and MIT, taps a reader's ability to represent meaning from text. The RCT has the advantage of not being confounded by individual differences in memory, or processing capacity, since all of the sentences being judged remain in full view while completing a test item. It also has the advantage of being adaptable across many sign systems, the test items could as easily be objects as opposed to sentences.