The ball floats in the liquid at a constant speed. How many times does the resistance force

The ball floats in the liquid at a constant speed. How many times does the resistance force acting on it differ from the gravity of the ball, if the density of the material from which it is made is 1.4 times less than the density of the liquid?

Given:

ro = ro1 * 1.4 – the density of the liquid (ro) is 1.4 times greater than the density of the ball (ro1);

g is the acceleration of gravity.

It is required to determine Fcopr / Fgravity – how many times the resistance force differs from the gravity force.

According to the condition of the problem, the ball floats up in the liquid at a constant speed, that is, it moves upward. Then, according to Newton’s first law:

Farchimedes = F gravity + Fcopr;

Fcopr = Farchimedes – F gravity;

Fsopr = ro * g * V – ro1 * V * g, where V is the volume of the body;

Fcopr = g * V * (ro – ro1).

Then:

Fcopr / F gravity = g * V * (ro – ro1) / (m * g) = g * V * (1.4 * ro1 – ro1) / (ro1 * V * g) =

= g * V * 0.4 * ro1 / (ro1 * V * g) = 0.4 times.

Answer: the force of resistance differs from the force of gravity by a factor of 0.4.