Suppose you have a pipe with circumference 8 cm and length 20 cm and that 8 turns of a wire are wrapped around the pipe. What is the lenght of the wire? (hint: it isnt 64cm) Thanks in advance...
2007-02-10 02:30:48 · 9 answers · asked by unpredictedmystery 3 in Science & Mathematics ➔ Mathematics
67.052218 cm
How to do it, is to unroll the pipe. What we then have is a 8 cm by 20 cm flat sheet that simply gets covered by the wire in a diagonal fashion. Since the wire goes around 8 times, the first 1/8 of the total leggth goes from the top left corner to the bottom but 1/8 of the length, which is 2.5 cm. Since the wire is following the diagonal, then it is SQRT(2.5^2 + 8^2) or SQRT(70.25) or 8.381527 cm in length. But this pattern repeats 8 times total, so we have 8 * 8.381527, for a total length of 67.052218 cm.
2007-02-10 02:45:30 · answer #1 · answered by Vincent G 7 · 1⤊ 0⤋
With a circumference of 8 cm, the diameter is 2.5 cm (rounded)
I assume the wire is travelling along the length of the pipe (20 cm) and accross the 2 ends (both being 2.5 cm)
This totals to be 8 * ( 2 * (20+2.5) ) = 360 cm or 3.6m
2007-02-10 10:38:03 · answer #2 · answered by docufreak 2 · 0⤊ 0⤋
I think it is figured as if you wrapped the wire around the pipe moving from one end to the other. Then imaginarily unroll the triangle created. The triangle would have a base of 64cm and height of 20cm. The length of wire would be the hypotenuse so sqrt( 20^2 + 64^2) = 67.05cm
2007-02-10 10:47:06 · answer #3 · answered by rscanner 6 · 1⤊ 0⤋
Yo cut the pipe longitudinally and put it in a plane. Then you have 8 diagonals, each one having 8 cm. on a side and 20/8 = 2,5 cm on the other side, so its length will be sqareroot((8^2+2,5^2).
Total lenght of the wire will be
8*sqroot(64+6,25) = 67.04 cm. approx.
It would be better to suppose a length of 48 instead of 20, for then
we will have 8*sqroot(64+36)=80 cm exactly.
2007-02-10 11:12:25 · answer #4 · answered by Jano 5 · 0⤊ 0⤋
It's a spiral, but if you were to unwrap it, you'd have a triangle whose hypotenuse is the wire, height is the height of the cylinder, and base that is 8 times the circumference.
2007-02-10 10:46:54 · answer #5 · answered by arbiter007 6 · 1⤊ 0⤋
64
2007-02-10 10:34:23 · answer #6 · answered by walter_b_marvin 5 · 0⤊ 1⤋
320
2007-02-10 10:37:50 · answer #7 · answered by Deja K 1 · 0⤊ 0⤋
It seems to me that there should be more information available, because otherwise, the answer is 64. 8*8.
2007-02-10 10:37:00 · answer #8 · answered by mradigan747 2 · 0⤊ 0⤋
i dont know the my answer will be correct but
at the first time i thought that should be 64cm but you said wrong so
ans is 96.8cm.
good luck
2007-02-10 10:47:06 · answer #9 · answered by Helper 6 · 0⤊ 0⤋