Mason notices that his boat sinks lower into the water in a freshwater lake than in the ocean. what could explain this?
a. the boat is more dense in salt water.
b. the boat is less dense in salt water.
c. salt water is less dense than freshwater.
d. salt water is more dense than freshwater.

Answer

D. Salt water is denser than freshwater.

Explanation

A boat is able to float on water because it experiences an upthrust upwards.

The magnitude of the upthrust depends on the density of the liquid.

When the liquid is denser the boat will experience a great upthrust as compared to when in a less dense liquid.

If the boat sinks lower in the freshwater than in salty water, then Salt water is more dense than freshwater.

D) Salt water is more dense than freshwater.

Explanation: Suppose that you have a glass of water, and you put a little amount of salt in it and mix it.

Now you may see that there is more matter in the glass (the volume of the solution inside the glass also may increase, but not in an appreciable magnitude compared with the increase in mass). And you may know, the density is calculated:

Density = Mass/volume

So if you have more mass in the same volume, this means that the density increases.

And is easier to float in a denser medium than in a low density medium (is easier to float in honey than in water, for example)

So if the medium if denser, the boat will float more easily.

Then the right answer is option D:  Salt water is more dense than freshwater

find the sum of the two horizontal vectors and the sum of the two vertical vectors

isoceles right angled triangle