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anonymous
 one year ago
Will give medal and fan :) thank you
question and photos below
anonymous
 one year ago
Will give medal and fan :) thank you question and photos below

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anonymous
 one year ago
Best ResponseYou've already chosen the best response.0The arcs in the photo (will give later on below) to the right appear to be paths of stars rotating about the North Star. To produce this effect, the photographer set a camera on a tripod and left the shutter open for a long time. If the photographer left the shutter open for a full 24 hours, each arc would be a complete circle. You can model a star’s“rotation” in a coordinate plane. Place the North Star at the origin.Let P(1, 0) be the position of the star at the moment the camera’s shutter opens.Suppose the shutter is left open for 2 hours and 40 min.(1)Find the angle of rotation that maps point P on to P’ 2. (2)What are the x and y coordinates of point P’ to the nearest thousandths? (3) Determine a translation rule that maps point P onto P

anonymous
 one year ago
Best ResponseYou've already chosen the best response.02 hr 40 min = \(2\frac{ 2 }{ 3 }\) hr In 24 hrs the rotation is 2π radians. Set up a proportion to find the angle of rotation between the P and P'. \[\frac{ 24 }{ 2\pi }=\frac{ 2\frac{ 2 }{ 3 } }{ \theta }\]

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Then you can use trig ratios to find the x and y coordinates of P' since the radius of the circle = the hypotenuse of the right triangle = 1

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0@peachpi can you explain more? I still don't understand

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0slight mistake \[rate = \frac{ distance }{ time }\] The rate of the rotation is the same for the whole 24 hours. It takes 24 hours to rotate 2π radians (or now that I think about it you probably want this in degrees, so 360°). We're trying to find the angle that corresponds to the time of \(2\frac{ 2 }{ 3 }\) hours. \[\frac{ 360° }{ 24~hours }=\frac{ \theta }{ 2\frac{ 2 }{ 3 }~hours}\] or if you wanted radians \[\frac{ 2pi }{ 24~hours }=\frac{ \theta }{ 2\frac{ 2 }{ 3 }~hours}\]

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0hummmm, so this is the rotation from point P to P'? @peachpi

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Θ is the angle of rotation

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0@peachpi there is 2 more question go with the proplem, can you slove it too?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0dw:1439692128942:dw

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Use what you get for x and y for the translation. P is at (1, 0). P' is at (x, y), Once you have x and y find the numbers you need to add/subtract to turn (1, 0) into (x, y)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0@peachpi Since I got the results is x = 0.643, y=0.776, I know the translation rule so I was just wondering if this right or not: T(x,y) = (x+0.643,y+0.776)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0The y would be right. For the x, you want to turn 1 into 0.643, so you'd have to subtract 0.357. So it's T(x, y) = (x  0.357, y + 0.776)
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