What is the buoyant force acting on the rock?

[mike2007]

A rock with a volume of 0.2m3 is fully sumberged in water with density of 1000kg/m3. What is the buoyant force acting on the rock?

Assume that gravity acts on the system
0.2m3*9.81m/s2 = 1.96
buoyant force = 1000kg/m3*1.96
= 1960N
?

 

[G01]

Check the units of your answer. You do not have the correct expression for buoyant force. The buoyant force on an object also depends upon the volume submerged:

$$F_b=\rho g V$$ where V is the volume submerged.

 

[mike2007]

Ok, i get it now. makes it a lot clearer.
thanks