formula
Formula of density: ρ=m/V (ρ means density, m means mass, and v means volume) When correctly understanding the density formula, we should pay attention to the conditions and the special meanings expressed by various physical quantities. From a mathematical point of view, there are three situations (judging right or wrong): when 1. ρ is fixed, and m is proportional to v; 2. When m is constant, ρ is inversely proportional to V; 3. When V is constant, ρ is proportional to m..
One kilogram of water turns into ice or one kilogram. Because mass is conserved. Therefore, the formula 2 m water =m ice is used.
P water *v water =p ice *v ice v ice =1000/0.8 =1250cm3.