Determine the metal required to make a 21 m long pipe if its inner and outer…
20232025
Determine the metal required to make a 21 m long pipe if its inner and outer diameter is 12 m and 10 m respectively.
- A.
2534 m^3
- B.
2843 m^3
- C.
726 m^3
- D.
2647 m^3
Attempted by 6 students.
Show answer & explanation
Correct answer: C
Clarification: outer diameter must be larger than inner diameter. We take outer diameter = 12 m and inner diameter = 10 m.
Formula: Volume of metal = (π/4) × (D_outer^2 − D_inner^2) × length
Compute squares: 12^2 − 10^2 = 144 − 100 = 44.
Multiply by length: 44 × 21 = 924.
Apply the factor π/4: (π/4) × 924 = 231π ≈ 725.654.
Final answer: approximately 726 m^3 (rounded).