Finding Volume of Region Inside Sphere and Cylinder in Cylindrical Coordinates

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The discussion focuses on calculating the volume of the region inside both a sphere defined by x^2+y^2+z^2=4 and a cylinder described by (x-1)^2+y^2=1 using cylindrical coordinates. One participant suggests limits for integration but is questioned about the correct interpretation of the cylinder's equation and the order of integration. Clarifications are requested regarding the integration limits, particularly for dz, dr, and dθ. It is emphasized that the proposed limits are incorrect and that a proper polar equation of the cylinder must be determined for accurate limits. The conversation highlights the importance of correctly setting up the integration limits in cylindrical coordinates for this volume calculation.
E&H12
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Find the volume of the region inside both the sphere x^2+y^2+z^2= 4 and the cylinder (x-1)+y^2=1using cylindrical coordinates.

I was thinking the inner limits would go from +(2-r) to - (2-r)
the middle intervals would go from 0 to 1
and the outer limits 0 to 2pi

is my approach correct
 
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E&H12 said:
Find the volume of the region inside both the sphere x^2+y^2+z^2= 4 and the cylinder (x-1)+y^2=1


using cylindrical coordinates.

I was thinking the inner limits would go from +(2-r) to - (2-r)
the middle intervals would go from 0 to 1
and the outer limits 0 to 2pi

is my approach correct

1. Did you mean the cylinder ##(x-1)^2 + y^2 = 1\, ##? I am assuming so.
2. You have to tell us what your order of integration is. For example are you describing the limits for ##dzdrd\theta\, ##?
3.If so, notice that ##\sqrt{4-r^2}\ne 2-r##
4. To get correct ##r,\theta## limits you need to find the polar equation of the cylinder and plot its trace in the xy plane. Your limits are wrong.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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