Final answer:
The student's questions involve calculations related to electric generators and motors, focusing specifically on factors such as induced voltage, frequency, angular velocity, and resistance. The key concepts required for solving these questions are electromagnetism and electrical engineering principles.
Step-by-step explanation:
The questions proposed by the student pertain to the operation and characteristics of electric generators and motors, a topic encompassing concepts from electromagnetism and electrical engineering. When analyzing electric generators, the relationship between the physical dimensions, rotational speed, the magnetic field, and the induced voltage are crucial. These factors are used to calculate key properties such as the generated voltage, frequency of the output voltage, and the strength of the magnetic field required for a specific output.
For instance, when examining a generator having a rotating coil within a magnetic field, the angular velocity and the number of turns of the coil are influential in determining the peak voltage produced by the device. For the question concerning a generator coil with 500 turns and an 8.00 cm diameter rotating in a 0.250 T magnetic field, the angular velocity in rpm required to produce a peak voltage of 480 V can be found using Faraday's Law of electromagnetic induction.
Additionally, understanding the concept of back emf and resistance in motors helps to analyze their performance. For electric motors, the back emf is an important factor that influences the current drawn by the motor and, consequently, its speed and power output. The resistance of an electric motor, which typically includes components like armature coils and field coils, also plays a significant role in determining the motor's operational characteristics.