Question

A hollow spherical shell is made of a metal of density 4.5/cm^3. if its internal and external diameters are 8cm and 9cm respectively, find the wieght of the shell

Answer 1

Answer:

Step-by-step explanation:

External diameter = 9 cm

External radius = 4.5 cm

Internal diameter = 8 cm

Internal radius = 4 cm

Volume of hollow spherical shell = 4/3×π(R²-r²)

                                                       = 4/3×3.14[(4.5)²-(4)²]

                                                       = 4/3×3.14[20.25-16]

                                                       = 4/3(3.14)(4.25)

                                                       = 4/3(13.35)

                                                       = 53.4/3

                                                       = 17.8 cm³

Density of metal = 4.5 g/cm³

Density = Mass/Volume

Mass of metal = Density×Volume

                       = 4.5 × 17.8

                       = 80.1 g