 # Question 1. Show that a unit speed meridian on a surface of revolut...

## Question

Show transcribed text

## Transcribed Text

Question 1. Show that a unit speed meridian on a surface of revolution (see Homework 4) is always a geodesic (HINT: Use Prop 4.17 in the notes). Use similar techniques to determine when a circle of latitude is a geodesic. Phrase your answer in terms of the tangent vector X 1 along the circle of latitude. Question 2. Let M be a surface, and let II be a plane that intersects M symmetrically (that is to say, the two sides of M on either side of II are mirror images of each other). Show that the curve == M n II must then be a geodesic (once it is parametrized by unit speed). (HINT: What does the symmetry condition tell you about n along 7? Give a visual of this situation, but no need for an analytic proof) Question 3. Show that any geodesic on the unit sphere (with full domain R) is a great circle (see Example 4.19). HINT: There may be several possible approaches, but one would be to use Homework 7 to help explain why // - . The general solution of this 2nd order ODE has two constants (constant vectors) of integration, and you should be able to use the fact that both and are unit vectors to help with these. Question 4. Suppose that (U) is a simple surface having 911 = 1 and 912 = 0 everywhere. Prove that in this case, u¹-curves (curves o Y U where Yu has constant u2 value) are geodesics. Question 5. Let (t) be a geodesic (with domain Rt for simplicity) that is NOT parametrized by arc length. Let S denote arc length and P : Rt Rs be the arc length reparametrization function S = (t), with inverse 0 : Rs Rt so that t = 0(s). Prove that the downstairs curve Y U (t) satisfies d²~k i d~² dt dyj dt dyk dy 2 d20 + dt² dt dt ds² ij for k = 1,2. Question 6. Following up on Example 5.3 in the notes, suppose again that M = S² and p = be the east pole, but this time define f S2 R U x y x2 + 3y + 4z Z If X = a is any tangent vector at p (here a, b are two constants), then compute f. b Question 7. What (linear) map is the Weingarten map at any point of the unit sphere? There should be a one-line explanation (you will be asked for a computational proof later).

## Solution Preview

These solutions may offer step-by-step problem-solving explanations or good writing examples that include modern styles of formatting and construction of bibliographies out of text citations and references. Students may use these solutions for personal skill-building and practice. Unethical use is strictly forbidden.

By purchasing this solution you'll be able to access the following files:
Solution.pdf.

\$75.00
for this solution

or FREE if you
register a new account!

PayPal, G Pay, ApplePay, Amazon Pay, and all major credit cards accepted.

### Find A Tutor

View available Differential Geometry Tutors

Get College Homework Help.

Are you sure you don't want to upload any files?

Fast tutor response requires as much info as possible.