Question

5. Consider the torus of revolution generated by rotating the circle z2 r 2, y = 0, (x a)2 about the z axis (a > r> 0). The parallels generated by the points (a + r, 0), (a - r, 0), (a, r) are called the maximum parallel, the minimum parallel, and the upper parallel, respectively. Check which of these parallels is а. A geodesic. b. An asymptotic curve c. A line of curvature

from Do Carmo.

Answer 1

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