Question

What is the buoyant force on 5kg solid object with density of 2×10⁴kg/m³ immersed in fluid with 5×10³kg/m³ density?

Answer 1

Buoyancy force can be calculated with the equation

`Fb = Vs × D × g`

where

• Fb = the buoyancy force,
• Vs = the submerged volume,
• D = the density of the fluid the object is submerged in,
• g = the force of gravity.

In this case, the weight of the ball is 5 kg and the density of the ball is 2× 10⁴kg/m³

Therefore the volume is given as

`v = (m)/(d) = \frac{5}{2 * 10 {}^(4) kgm {}^( - 3) } \\ v = \: (5)/(20000) m {}^( - 3)`

Substituting the given values in the equation, we get,

`Fb=Vs * D * g \\ Fb = (5)/(20000) m {}^(3) * 5000kgm {}^( -3) \\ *10ms {}^( - 2) \\ = 12.5N`

Hence, the force of buoyancy is 12.5N.