A plastic ball has a volume of 300 cm3 and a mass of 30 g. What fraction of the ball's volume will float above the surface of a lake of fresh water?
To determine the fraction of the ball's volume that will float above the surface of a lake of fresh water, we need to compare the density of the ball with the density of water.
Density is the ratio of an object's mass to its volume. The formula for density is:
Density = Mass / Volume
In this case, the density of water is approximately 1 g/cm3. Given that the mass of the plastic ball is 30 g and its volume is 300 cm3, we can calculate its density as follows:
Density of ball = 30 g / 300 cm3 = 0.1 g/cm3
Now, let's compare the density of the ball with the density of water. If the density of the ball is less than the density of water (i.e., less than 1 g/cm3), the ball will float. Otherwise, if the density of the ball is equal to or greater than the density of water, it will sink.
In this case, since the density of the ball is 0.1 g/cm3, which is less than the density of water, the ball will indeed float.
To determine the fraction of the ball's volume that will float above the surface of the water, we need to find the ratio between the volume of the ball that is submerged in water and the total volume of the ball.
Since the density of the ball is less than the density of water, the entire ball will float. Therefore, none of its volume will be submerged, and the fraction of the ball's volume that will float above the surface of the water is 1, or 100%.
In summary, the entire volume of the plastic ball will float above the surface of the water, so the fraction of the ball's volume that will float is 1 or 100%.