Physics - Polar Coordinates: Describe the locus of points

AI Thread Summary
The discussion focuses on understanding the locus of points in polar coordinates. For the points given with r = 4, the locus forms a circle centered at the origin with a radius of 4. Additionally, when describing the locus for fixed angles such as theta = 60, the result is a straight line emanating from the origin at that angle. The participants clarify that the locus for varying r values at a fixed angle results in a radial line. Overall, the thread emphasizes the geometric interpretations of polar coordinates in relation to circles and lines.
bobraymund
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Hi,

So, I was doing my physics summer work and had no idea what the following question was talking about:

Homework Statement



For the following polar coordinate points:

(4, 0) (4, 60) (4, 90) (4, 135) (4, 180) (4, 270)

Describe the locus of points for which

a) r = 4
b) r = a

An image, for reference, can be seen http://img43.imageshack.us/img43/6422/0815002025.jpg .


The Attempt at a Solution



I was thinking that the answer would be merely saying something like (4, 0) (4, 60) (4, 90) (4, 135) (4, 180) (4, 270), because those are all the points at r = 4. But I have no idea. :(

Thanks for the help!
 
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The locus of the points is a circle with center (0, 0) and radius 4.
 
Ah, thanks! that makes sense!

So, then this one here: http://img413.imageshack.us/img413/6007/0815002113.jpg

Would that be a line with like slope ?

Edit: the second question states: describe the locus of points for which theta = 60 and theta = theta1 (where theta1 is a fixed angle)
 
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Yes. It is a straight line.
 
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