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Sirsh
Jun20-10, 10:28 PM
Hello all.

This is not homework, i stumbled upon it looking for information for my physics.. I have some background in calculus and am just wondering if anyone would have any idea on how you'd solve this area problem.. all i have is a picture of it and not any equations of the lines.

Thanks.

http://upload.wikimedia.org/wikipedia/commons/thumb/f/f8/Green%27s-theorem-simple-region.svg/429px-Green%27s-theorem-simple-region.svg.png
berkeman
Jun20-10, 10:37 PM
Hello all.

This is not homework, i stumbled upon it looking for information for my physics.. I have some background in calculus and am just wondering if anyone would have any idea on how you'd solve this area problem.. all i have is a picture of it and not any equations of the lines.

Thanks.

http://upload.wikimedia.org/wikipedia/commons/thumb/f/f8/Green%27s-theorem-simple-region.svg/429px-Green%27s-theorem-simple-region.svg.png

Sure. Print it, cut out the area, weigh the paper cutout (and weigh a full piece of paper with known dimensions). I still remember my undergrad Physics TA telling me about this technique...
berkeman
Jun20-10, 10:38 PM
Oh, and what is the context of the question?
Sirsh
Jun20-10, 10:42 PM
Wow that's a very smart idea haha. Um, it was just finding out the way to calculate the area of the region D. Is there anyway mathmatically?

My thoughts are to take away the area of C1 from a-b from the area of C3 from a-b with integration.
berkeman
Jun20-10, 10:44 PM
Wow that's a very smart idea haha. Um, it was just finding out the way to calculate the area of the region D. Is there anyway mathmatically?

My thoughts are to take away the area of C1 from a-b from the area of C3 from a-b with integration.

You said you had no equations. What do you plan to integrate?
Mark44
Jun20-10, 10:52 PM
I notice that the curves that bound the region are marked with arrows. Is this some kind of a path integral? I seem to remember that the line integral along a closed path in a conservative field is zero.
Sirsh
Jun20-10, 11:13 PM
Ah yes, i don't my msitake.

http://en.wikipedia.org/wiki/Green%27s_theorem

That's the webpage I got the picture from..
Mark44
Jun20-10, 11:20 PM
Ah yes, i don't my msitake.
??? What are you saying here?


http://en.wikipedia.org/wiki/Green%27s_theorem

That's the webpage I got the picture from..