I cut the cylinder at a 45 degree angle

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Question from Shannon:

I have a cylinder with a radius of 2' 1 5/8".
How do I calculate the radius increase when I cut the cylinder at a 45 degree angle?

Hi Shannon,

First I would convert the radius to inches in decimal form. I get 25.625 inches.

cylinder

On the diagram C is in the centre of the cylinder. The triangle ABC is a right triangle and since the measure of the angle CAB is 45 degrees |BC| = |CA| = r, the radius of the cylinder. Using Pythagoras theorem

|BC|² + |CA|² = |AB|²

|AB|² = r² + r² = 2r²

and hence |AB| = √2 r = 1.4142 × r.

Harley

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