Answer the following question.
A current-carrying conductor
A student performed an experiment by placing a compass needle below a straight copper wire connected to two \(1.5\ V\) cells and a plug key. When the key was plugged in, the current flowed from north to south, and the north pole of the compass needle deflected towards the east.
Another student repeats the same experiment but observes that the compass needle does not deflect.
Which of the following is the most likely reason?
Which of the following is the most likely reason?