Posted by Alona on .
Will a 7.25 kg ball with a diamter of 22 cm float in water? I know that the radius is 11 cm and that the density of water is 1000kg/m^3 and I got that it will float but it just doesn't sound right. Could anyone help please?

physics (easy) 
drwls,
Calculate the mass of a 11 cm radius sphere of water.
(4/3) pi r^3 = 16,726 cm^3 = 1.672*10^2 m^3
Mass (if H2O) = 16.726 kg
The ball is lighter than water and will float.
You could have also just calculated the density of the actual ball, which is 7250 g/16,726 cm^3 = 0.433 g/cm^3. Water's density is 1.00 g/cm^3