Final answer:
The scale will show a lower weight than 260 N when the brass is submerged in water due to the upward buoyant force; without the volume of the brass, the exact new reading cannot be determined.
Step-by-step explanation:
When a piece of brass is submerged in water, the scale will read a lower value than when it is hanging in air due to the buoyant force exerted by the water on the brass. This force acts in the upward direction and is equal to the weight of the water displaced by the brass, according to Archimedes' principle. Since the scale initially reads 260 N in air, the submerged reading will be the initial weight minus the weight of the water displaced. To find the exact new reading, the volume of the brass must be known to calculate the weight of the water displaced. Without the volume, we cannot determine the exact reading, but it will certainly be less than 260 N.