question_answer

A cubical box is to be constructed with iron sheets 1 mm in thickness. What can be the minimum value of the external edge so that the cube does not sink in water? \[[{{\delta }_{iron}}=8000kg/{{m}^{3}},{{\delta }_{water}}=1000kg/{{m}^{3}}]\]

A) 4.8cm

B) 5.8cm

C) 6.9 on

D) 7.3cm