Because an object will float if the bouyant force (3.5 N) is greater than the weight of the submerged object (5 N) - so in this case the object would sink.
But does the bouyant force change if the volume is doubled?
Homework Statement
An object weighing 5.0 Newtons displaces a certain volume of water when dropped into a large beaker of water. The weight of the displaced water is 3.5 Newtons. The object is free to sink or float. What would be the value of the bouyant force is another object twice the...