A plastic bobber just barely floats in water. If it weighs 2N in the air, what is its volume
If the body "barely floats" in water, that means that the density is the same as that of water, equal to 1 kg/l.
The weight, mg = 2N,
its mass, m = 2N/g = 0.204 kg
Therefore the volume is 0.204 kg / (1 kg/l)
= 0.204 l. = 204 cm³
To find the volume of the plastic bobber, we can use Archimedes' principle, which states that the buoyant force acting on an object submerged in a fluid is equal to the weight of the fluid displaced by the object.
Since the bobber is just barely floating, the buoyant force acting on it is equal to its weight in air, which is 2N. Therefore, we can conclude that the bobber displaces 2N of water.
Now, we need to convert the weight of water into volume. We can use the fact that the density of water is approximately 1000 kg/m³ or 1000 N/m³.
The formula to calculate the volume is:
Volume = Weight / Density
Substituting the values:
Volume = 2N / 1000 N/m³
Volume = 0.002 M³ or 2 Liters
Therefore, the volume of the plastic bobber is 0.002 cubic meters or 2 liters.