Question

A metallic sphere of radius 2.0 cm is completely immersed in water. Find the force of buoyancy on it.

Answer 1

Given Data:

Radius of metallic sphere, $r=2cm=0.02m$

Step 1: Buoyant Force:

The force of buoyancy is written as: $\text{F = ρgV}$

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

Here $g={10ms}^{-2}$

$V=\frac{4}{3}\pi r^3=\frac{4}{3}\pi \times {\left(0.02\right)}^3=33.5\times {10}^{-6}{m}^3$

And density ρ (for water) $=997kg{m}^{-3}$

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

Thus, buoyant force,

$F=997\times 33.5\times {10}^{-6}\times 10=0.333N$