In a lead pipe 4.2 m long , the external diameter is 5.4 cm and the thickness of the pipe is 3 mm. Find the weight of the pipe , if 1 cm3 of lead mass is 25 grams . ( use )
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Correct answer: A
Explanation
The correct answer is option 1 i.e. 50.49 kg.
Length = 420 cm
Outer radius (R) = 2.7 cm
Inner radius (r) = 2.4 cm
Density = 25 g/cm³
π = 22/7
Volume = π × h × (R² – r²)
= (22/7) × 420 × (7.29 – 5.76)
= (22/7) × 420 × 1.53 = 2019.6 cm³
Weight = 2019.6 × 25 = 50,490 g = 50.49 kg