A belt 15 feet long is tightely tied to cylinder.The dia of each circle is 1feet.the dist betw 2 centers is??

Question

A belt which is 15 feet long is tightely tied to a cylinder. The diameter of each circle (which is at the both ends of the cylinder) is 1 feet. What is the distance between the centers of 2 circles???

Answer 1

i m directly making eqution

15 - 4pie *r = 1
r=7/2pie diameter = 7/pie

apply phythagorous theorem

(1)^2 + (7/pie)^2

solve this and u will get the answer

Answer 2

Curved Surface Area of cylinder = Length of belt
=> 2*pi*r*h = 15 feet
=> 2*(22/7)*(1/2 feet)*h = 15 feet
=> h = 15*(7/22)
=> h = 4.772727272....
=> h = 4.78 feet.

Answer 3

Since the belt is tightly tied to cylinder and assuming that the belt has zero area(only length), we can assume that length of the belt is NUMERICALLY equal to total surface area of the cylinder.
The total surface area of the cylinder is (curved surface area+circular base areas of the cylinder)=(2pi.r.h)+(2pi.r^2) where r is the radius to the circular base( 1/2 feet) and h is the height of the cylinder.
=>15=(2pi.r.h)+(2pi.r^2)
=>15=2pi.r(h+r)
=>15=2pi.(1/2){h+(1/2)}
=>15=pi.{(2h+1)/2}
=>30=pi(2h+1)
=>30/pi=2h+1
=>{(30/pi)-1}/2=h
=>h=4.277 ft

Answer 4

um, i got 6.5 by doing it a different way, maybe i didnt understand the Q. I just subtracted 2 feet from 15 and then divided the answer by 2.

Answer 5

let the distance between the two centers be x
so 2pi r + 2x = 15
2X 3.14 X 1 + 2x = 15
2x = 15 - 6.28 = 8.72
x = 8.72/2
= 4.36 ft