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Physics Query

When a ball falls through a liquid at constant speed, what are the forces acting on it. I know that the forces are viscous drag, weight and upthrust but how do they differ in size to each other? Can anyone show with the help of a diagram.
Original post by ranataw
When a ball falls through a liquid at constant speed, what are the forces acting on it. I know that the forces are viscous drag, weight and upthrust but how do they differ in size to each other? Can anyone show with the help of a diagram.


If it's a constant speed, the downwards force (weight) is equal to the sum of the upwards forces (drag and upthrust). The exact values of drag and upthrust would vary depending on the density of the ball and the viscosity of the liquid.

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