We study certain linear representations of the knot group that induce augmentations in knot contact homology. This perspective enhances our understanding of the relationship between the augmentation polynomial and the A-polynomial of a knot. For example, we show that for 2-bridge knots the polynomials agree and that this is never the case for (non-2-bridge) torus knots, nor for a family of 3-bridge pretzel knots. In addition, we obtain a lower bound on the meridional rank of the knot. As a consequence, our results give a new proof that torus knots and a family of pretzel knots have meridional rank equal to their bridge number.
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