Question

One cubic meter (1.0 m3) of aluminum has a mass of 2700 kg, and a cubic meter of iron has a mass of 7860 kg.. Find the radius of a solid aluminum sphere that has the same mass as a solid iron sphere of radius 2.57 cm.. Answer in units of cm

Answer 1

4/3 · 2.57³ π · 7,860 = 4/3 · r³ π · 2,700  / : 4/3 π
2.57³ · 7860 = r³ · 2,700
r³ = 2.57³ · ( 7,860 : 2.700 ) = 2.57³ · 2.911111...    /∛
r ≈ 2.57 · 1.428 = 3.67 cm 
Answer: Radius of a solid aluminium sphere is 3.67 cm.