The difference between inside and outside surfaces of a cylindrical tube 14 cm long is 88 sq. cm. If the volume of the tube is 176 cubic cm, find the inner and outer radii of the tube.

Question

Philoid · Accepted Answer

Given,

Difference between inner and outer surface area of cylindrical tube = 88 cm²

Length of tube = 14 cm

Volume of tube = 176 cm³

= 2πRh – 2πrh = 88

= 2πh(R-r) = 88

= R-r = ………(i)

And, 2π(R²-r²)h = 176

= (R+r) (R-r) =

= R+r = 4 cm ………..(ii)

From equation (i) and (ii)

= 2R = 5 = R = 2.5cm

= r = 4-2.5 = 1.5 cm