Physics
Physics
Problem
An alternating-current generator has to supply an rms emf of at a frequency of . The generator uses a uniform magnetic field of and a rectangular coil of area . a. (i) Find the speed of rotation of the coil in revolutions per minute. b. (ii) Calculate the minimum number of turns required in the coil to meet the emf specification.Intuitive explanation
The key is connecting the generator's physical design to the electrical output it produces. An AC generator works by rotating a coil through a magnetic field, inducing an emf that varies sinusoidally with time—the peak value depends on the field strength, coil area, and rotation rate. You need to find how many coil turns are required so that the rms voltage (the effective steady voltage) reaches exactly 220 V at the given frequency.
Intuitive explanation
The key is connecting the generator's physical design to the electrical output it produces. An AC generator works by rotating a coil through a magnetic field, inducing an emf that varies sinusoidally with time—the peak value depends on the field strength, coil area, and rotation rate. You need to find how many coil turns are required so that the rms voltage (the effective steady voltage) reaches exactly 220 V at the given frequency.