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प्रश्न
The inner diameter of a cylindrical wooden pipe is 24 cm and its outer diameter is 28 cm. The length of the pipe is 35 cm. Find the mass of the pipe, if 1 cm3 of wood has a mass of 0.6 g.
`["Assume "pi=22/7]`
उत्तर
Inner radius (r1) of cylindrical pipe = (24/2)cm = 12 cm
Outer radius (r2) of cylindrical pipe = (28/2)cm = 14 cm
Height (h) of pipe = Length of pipe = 35 cm
`"Volume of pipe "= pi(r_2^2-r_1^2)h`
`=[22/7xx(14^2-12^2)xx35]cm^3`
= 110 x 52 cm3
= 5720 cm3
Mass of 1 cm3 wood = 0.6 g
Mass of 5720 cm3 wood = (5720 × 0.6) g
= 3432 g
= 3.432 kg
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