A ball moves downward through a liquid at steady speed. Three forces act on it: upthrust, drag-force and weight. Which statement is correct?
- AThe drag-force increases with increasing depth.
- BThe drag-force is equal to the sum of the upthrust and weight.
- CThe upthrust is constant with increasing depth.
- DThe weight is greater than the sum of the drag-force and the upthrust.