Question

A test tube has diameter 20 mm and height is 15 cm. The lower portion is a hemisphere. Find the capacity of the test tube. (π = 3.14)

Answer 1

Radius of test tube (r) = 20/2 = 10 mm = 1 cm

Height of test tube = 15 cm

Upper portion of test tube is cylinder and lower portion of test tube is hemisphere.

Height of cylinder (H)= h-r = 15 - 1 = 14cm

Volume of test tube = Volume of cylinder + Volume of hemisphere

                                 = `pir^2H+2/3pir^3`

                                  = `(3.14)(1)^2(14)+2/3(3.14)(1)^3`

                                  = 43.96 + 2.09

                                  = 46.05 cm³

Capacity of test tube is 46.05 cm³.