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Rod of length 30.50 cm has linear density (mass per length) given by = 50.0 21.0x where x is the distance from one end, and is measured in grams/meter. (a) what is its mass? g (b) how far from the x = 0 end is its center of mass?

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Final answer:

The mass and center of mass of a rod with a linear density given by μ(x) = 50.0 + 21.0x can be found by integration of the linear density over the rod's length for mass, and by using the definition of center of mass for a continuous distribution, divided by the total mass, for the position of the center of mass.

Step-by-step explanation:

To find the mass of a rod with variable linear density, we integrate the linear density function over the length of the rod. In this case, the linear density (μ) is given as a function of x: μ(x) = 50.0 + 21.0x grams/meter. The length of the rod (L) is 30.50 cm or 0.305 meters. Therefore, the mass (m) is found by integrating the linear density function from 0 to L:

m = ∫0L μ(x) dx = ∫00.305 (50.0 + 21.0x) dx

Thus, the mass is given by the antiderivative evaluated from 0 to 0.305 meters.

To find the center of mass (xcm) of the rod, we use the definition of center of mass for a continuous distribution:

xcm = (1/m) ∫0L x μ(x) dx

We plug in the given linear density function and integrate from x=0 to x=L. After finding the integral, we divide by the total mass of the rod to find the position of the center of mass.

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