For an object to float in water, its density must be:
Aless than the density of the water
Bequal to the density of the water
Cgreater than the density of the water
Dindependent of the water's density
Answer & Solution
Correct answer: A. less than the density of the water
1. Whether an object floats depends on how its density compares with the fluid's.
2. An object less dense than the fluid displaces a weight of fluid equal to its own before it fully submerges.
3. At that point the upthrust matches its weight and it floats.
4. An object denser than the fluid cannot displace enough weight, so it sinks.
5. Equal densities leave the object suspended within the fluid rather than floating on the surface.
_Source: NECTA CSEE 2022 Physics 031, Question 1: Multiple Choice, item (ii)_
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