Question

Gerald is fishing. He uses a bobber that floats on the surface to show him if the line is being moved, and a lure that sits below the surface to attract fish.

Which statement accurately describes the densities of these two items?

The bobber and lure are more dense than the water.
The bobber and lure are less dense than the water.
The bobber is more dense than the water, and the lure is less dense than the water.
The bobber is less dense than the water, and the lure is more dense than the water.

Answer 1

The correct answer is-The bobber is less dense than the water, and the lure is more dense than the water.

Step-by-step explanation:

Density plays an important role in floating and sinking of an object in the water. If an object density is more than water then the object will sink in the water and if the density of an object is less than water then it will float on the surface of the water.

So here the bobber floats on water because it is less dense than water and lure sinks because it has more density than water. Density is equal to mass/volume so it is inversely proportioned to volume therefore when volume increases with the same mass than the density decreases.

Therefore the right answer is -The bobber is less dense than the water, and the lure is more dense than the water.

Answer 2

Answer: Option (d) is the correct answer.

Step-by-step explanation:

Density is defined as mass divided by volume.

Mathematically, Density =
`(mass)/(volume)`

So, more is the mass of a substance more will be its density. As a result, a substance with more density will sink if its density is less that the liquid in which it is immersed.

Similarly, less is the mass of a substance less will be its density. As a result, a substance with less density will float if its density is less than the liquid in which it is immeresed.

Therefore, when bobbler floats at the surface of water then it means its density is less than the density of water. Whereas lure sinks below the surface of water so, it has more density than water.

Thus, we can conclude that the bobber is less dense than the water, and the lure is more dense than the water.