2009-10-26, 01:04 PM
(This post was last modified: 2009-10-27, 01:16 AM by KajitiSouls.)
I'M IN DIS THREAD, NECRO-POSTING UR PROBLEMS!!
There's one problem that's been bothering me for a while. No picture this time xD
A 1'' steel plate is taken, and a 3/4'' hole is drilled out. Then a countersink drill bit (90 degrees at the point) replaces the regular drill bit and bores out even more steel. The area it would normally have drilled out is in the shape of a simple cone, and the base diameter is 1 1/4''. Both drills were used at the exact same spot. How much steel was bored out by the countersink drill bit?
My first try at it was integration and revolutions, but for some reason it wouldn't work out. I managed to find the answer with the Pappus-Guldinus theory. But I want to know what is the proper integral that defines the answer?
There's one problem that's been bothering me for a while. No picture this time xD
A 1'' steel plate is taken, and a 3/4'' hole is drilled out. Then a countersink drill bit (90 degrees at the point) replaces the regular drill bit and bores out even more steel. The area it would normally have drilled out is in the shape of a simple cone, and the base diameter is 1 1/4''. Both drills were used at the exact same spot. How much steel was bored out by the countersink drill bit?
My first try at it was integration and revolutions, but for some reason it wouldn't work out. I managed to find the answer with the Pappus-Guldinus theory. But I want to know what is the proper integral that defines the answer?