A coil with a wire with open ends is brought into rapid rotation; a potential difference has arisen between its ends, this happens if.
The answer to the question posed in the original question is to have the skills to apply common physical laws and formulas. In accordance with the general rules of the course of physical phenomena for the occurrence of the situation described in the initial task, the coil must be in a magnetic field. In accordance with the law of induction, a magnetic field is characterized by the presence of a current, and, therefore, an electromotive force.
Answer. The coil must be in a magnetic field.
One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.