Internal radius of hollow spherical shell
(r_{1}) = 3 cm
External radius of hollow spherical = (r_{2}) = 5 cm
Volume of hollow spherical = 4/3π(r_{2}^{3} – r_{1}^{3})
= 4/3π[(5)^{3} – (3)^{3}]
= 4/3π(125 – 27)
= (4π × 98)/3 = 392π/3 cm^{3}
Volume of cylinder = Volume of hollow sphere
8πr^{2}/3 = 392π/3
r^{2} = 392π × 3/8π × 3
r^{2} = 49
r = √49
r = 7 cm
The diameter of cylinder = 2r = 2 × 7 = 14 cm