We are looking for the dimensions of the original rectangular sheet metal, not the new cylindrical ';stovepipe';. Please show work so that I will know how to solve this problem.
I AlWAYS select the best answer. Thank you.A rectangular sheet metal w/ an area of 1200 in虏 is bent into a cylinder w/ volume of 600 in鲁. Dimensions?
cylinder V = 蟺r虏h
600 in鲁 = 蟺r虏h
cylinder side area = circumference x h = 蟺dh = 2蟺rh
1200 in虏 = 2蟺rh
600 in虏 = 蟺rh
2 equations 2 unknowns
蟺r虏h = 600
蟺rh = 600
h = 600/蟺r
蟺r虏(600/蟺r) = 600
lots of things cancel
r = 1 inch
h = 600/蟺r = 600/蟺 = 191 inch
check
V = 蟺r虏h = 蟺1虏191 = 600
A = 2蟺rh = 2蟺191*1 = 1200
.A rectangular sheet metal w/ an area of 1200 in虏 is bent into a cylinder w/ volume of 600 in鲁. Dimensions?
Let's call the sides of the sheet a and b.
When you bend it to a cylinder, a will make up the height of the cylinder, whereas b will be the circumference of the ';ground floor';.
Information given is therefore:
a * b = 1200
b虏 * [pi] / 2 * a = 600
Try ro solve it like this:
a = 1200 / b -%26gt; substitute a with b
b虏 * [pi] /2 * 1200/b = 600
b虏 * [pi] * 1200/b = 1200
b * [pi] * 1200 = 1200
b = 1200 / 1200*[pi]
b = 3,142
a = 1200/b = 1200/3,142 = 381,971
To check if its correct:
a * b* = 3,142 * 381,971 = 1200
Hope I didn't make any mistakes ;)
volume of cylinder = pi()*r^2*h/4 = 600
rectangle one edge = height, other edge = circumference
area of rectangle = 2*pi()*r*h = 1200
h = 1200/(2*pi()*r)
from volume eqn. h = (600*4)/(pi()*r^2
so (2400)/pi()r^2 = 600/(pi()*r
or 4/r^2 = 1/r
or 4r = r^2
4 = r
h = 47.75
rectangle = 1200 = h*w, w = 1200/47.75 = 25.13
check, circumference = 2*pi()*r = 8*pi() = 25.13
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