## anonymous one year ago Estimate the angle of rotation of the stars in the time-lapse photo. http://cds.flipswitch.com/tools/asset/media/111660

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1. anonymous

2. anonymous

@dan815

3. anonymous

Im not sure if its 90 or 180

4. anonymous

If you were to create an angle i'm confused

5. anonymous

From what angle are we looking at it from?

6. anonymous

Time lapse photography is made by placing a camera on a tripod and keeping the camera’s shutter open for a long time. If the camera is pointed in the direction of the stars, the stars appear to rotate around Polaris, also known as the North Star or the Pole Star.

7. anonymous

thats all it gave me

8. anonymous

would it be 90

9. anonymous

I think you are correct, but I'm not a 100% sure.

10. anonymous

okay thank you very much

11. anonymous

|dw:1438312164441:dw| so this is what it may look like right, as it's pointed towards the stars, and is rotating around polaris, so that must be 90 degrees.

12. anonymous

Maybe not exactly, should be close to that...what do you think

13. anonymous

yeah thats what I though and the options were 30, 45, 90, and 180 so i thought it was 90 or 180

14. anonymous

Ok cool, I think that makes sense :) we are upon agreement, but in any case could you post the right answer when you're done this problem, I'm still skeptical.

15. anonymous

I would, but it's a project and doesn't tell me if it's right or wrong Im sorry.

16. anonymous

there was another question

17. anonymous

Use your answer from the previous question to estimate the length of time that the camera’s shutter was open. The shutter was open for ____ hours. (Round your answer to the nearest hour and enter only the number.)

18. anonymous

If the shutter is open for 24 hours, the stars appear to make one complete rotation around Polaris.

19. anonymous

No worries, so 360 is 24 hours, so all we have to do is $\frac{ 90 }{ 360 } = ...$

20. anonymous

You just have to convert it in hours, that shouldn't be too bad

21. anonymous

ohhh wow thats pretty easy just overthinking it thank you. Convert it from min to hours correct?

22. anonymous

Im sorry thank you I appreciate the help

23. anonymous

$\frac{ 90 }{ 360 } = 0.25$ that means it's 25% of 24 hours, so now just multiply by 24 to get the answer in hours, 0.25(24).

24. anonymous

No problem!

25. anonymous

to get 6

26. anonymous

Perfect

27. anonymous

thank you :)

28. anonymous