(6) Mass from linear density. Given a rod whose linear density function p(x) (in mass per unit length) measures the density at the value z over a region from a = a to z = b, mass is defined by mass - (1) mass= Kg To visualize this with example sets of units: - P(x) p(x) dx. m (2) mass - pla) dar 02. in Kg/m oz./in Consider a thin rod oriented on the positive x-axis over the interval [1, 3) with linear density p(x) = 2x + 3. Determine the mass of the rod.