[amp_mcq option1=”quiet” option2=”noisy” option3=”machine with large air gap lengths is comparatively A. quiet B. noisy C. either of the above” option4=”none of the above” correct=”option1″]
The correct answer is: A. quiet.
A DC machine with a large air gap length is comparatively quiet because the air gap acts as an insulator, which reduces the amount of noise generated by the machine. The air gap also helps to improve the efficiency of the machine by reducing the amount of power lost to eddy currents.
The other options are incorrect because a DC machine with a large air gap length is not noisy.