Дано:
а=40см=0,4м
р=7800кг/м3
<span>g=</span><span>9,8м/с2=</span><span>10м/с2</span>
Р-?
<span>P=mg, </span>
<span><span> </span>m=p*V, </span><span><span> </span></span><span>V=a*a*a, </span><span><span> </span></span><span>V=0,4*0,4*0,4=0,064м3,</span>
<span>m=7800*0,064=499,2кг</span>
<span>Р=499,2*10=4992Н</span>