Parameterization of the Circle

  • Thread starter Thread starter vanitymdl
  • Start date Start date
  • Tags Tags
    Circle
Click For Summary
The discussion focuses on determining the time it takes for a particle to move from the point (1,0) to (0,1) using three different parameterizations of a circle. For the first parameterization x1(t) = (cos(t), sin(t)), the time is calculated by finding t values corresponding to these points, specifically t = 0 for (1,0) and t = π/2 for (0,1), resulting in a time of π/2. The second parameterization x2(t) = (cos(3t), sin(3t)) requires finding t = 0 for (1,0) and t = π/6 for (0,1), leading to a time of π/6. The third parameterization x3(t) = (sin(t), cos(t)) gives t = π/2 for (1,0) and t = π for (0,1), resulting in a time of π/2. The discussion emphasizes the need to calculate specific t values for each parameterization to determine the corresponding travel times.
vanitymdl
Messages
64
Reaction score
0

Homework Statement



Consider the following parameterization of the circle:
a) x1 (t) = (cost, sint)

b) x2 (t) = (cos3t, sin3t)

c) x3 (t) = (sint, cost)

How long does it take point a particle to go from (1,0) to (0,1) for each parameterization.

Homework Equations





The Attempt at a Solution


(cos,sin) of (1,0) is 2pi then (cos, sin) of (0,1) is pi/2

how would I figure out the time it takes?
 
Physics news on Phys.org
vanitymdl said:

Homework Statement



Consider the following parametrization of the circle:
a) x1 (t) = (cost, sint)

b) x2 (t) = (cos3t, sin3t)

c) x3 (t) = (sint, cost)

How long does it take point a particle to go from (1,0) to (0,1) for each parametrization.

Homework Equations



The Attempt at a Solution


(cos,sin) of (1,0) is 2pi then (cos, sin) of (0,1) is pi/2

how would I figure out the time it takes?
For each parametrization find a value of t for which x(t) = (1, 0), then find the next greater value of t for which x(t) = (0, 1) .
 
Tricky wording. :smile:
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

Similar threads

  • · Replies 21 ·
Replies
21
Views
4K
  • · Replies 35 ·
2
Replies
35
Views
4K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
Replies
3
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 2 ·
Replies
2
Views
4K
Replies
1
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 4 ·
Replies
4
Views
2K