Question

what is the mass of a metal sphere of radius 3.0 centimetre if its density is 7.0 gram​

Answer 1

d=7g/cm^3 ; r= 3

d = m/v

m=d x v

m= d x 4÷3πr^3

$volume \: sphere \: = 4 \div 3\pi {r}^{3}$

m= 7 x 4/3 x 22/7 x 3 x 3 x 3

m= 4 x 22 x 9 = 792 g

m= 0.792 kg