Question

a metallic sphere of radius 2cm is completely immersed in water .find the force of buoyancy in it

Answer 1

The force of buoyancy is written as 

  F = ρgV

where ρ is the density of the fluid, g is the acceleration due to gravity and V is the volume of the sphere.

Here g = 10 m/s2

 V = (4/3)πr3 and r = 2 cm = 0.02 m

so, V = 1.67 m3

and density ρ (for water) = 997 kg/m3

so, the buoyant force can simply be calculated by substituting the above values.

thus,

 buoyant force,    F = 16649.9 N

Answer 2

Answer:

Explanation:

Volume of sphere = 4/3 X π X r³

= 4/3 X 22/7 X (2)³

= 4/3 X 22/7 X 8

Density of water = m/v

1 g/cm³ = m/704/21 cm³

m = 704/21 g = 33.523 g = 0.03352 kg

Bouyant force = weight of liquid displaced by that object

W = mg

= 0.03352 X 9.8

= 0.3285N

Therefore Bouyant force = 0.328