Question

1. what do you notice about the location of energy in this picture?
2. if 80 ml of the warmer salt water has 91 g of mass, what is its density?
3. if 80 ml of the colder fresh water has 85 g of mass, what is the density?
4. which of these will sink toward the bottom and why? which one is more dense?
5. how is the warmer water moving toward the glacier an example of convection?
6. how might the berm lessen this effect if it is built? would it be more important for the berm to be up where the iceberg is or near the bottom? why?
7. why do scientists use significant figures?

Explanation:

Step1: Analyze question 1

Energy is mainly in the form of heat in the warmer water layers. The warmer water - ice interactions near the glacier and at depth indicate energy transfer.

Step2: Solve question 2

The formula for density $
ho=\frac{m}{V}$. Given $m = 91$ g and $V=80$ ml. So, $
ho=\frac{91}{80}=1.1375$ g/ml.

Step3: Solve question 3

Using the density formula $
ho=\frac{m}{V}$ with $m = 85$ g and $V = 80$ ml. Then $
ho=\frac{85}{80}=1.0625$ g/ml.

Step4: Solve question 4

The warmer salt - water is more dense ($1.1375$ g/ml) compared to the colder fresh - water ($1.0625$ g/ml). The warmer salt - water will sink because denser substances sink in less dense substances.

Step5: Solve question 5

Warmer water is less dense and rises, while cooler water is denser and sinks. In the picture, the warmer water moves towards the glacier, replacing the cooler water. This is a classic example of convection where there is a transfer of heat due to the movement of a fluid (water).

Step6: Solve question 6

A berm could act as a barrier to the flow of warmer water towards the glacier. If built near the bottom, it would be more effective as the warmer water is at depth and is the main contributor to the melting of the glacier. Building it near the iceberg would mainly affect surface - level water movement, while the deeper, warmer water would still be able to reach the glacier.

Step7: Solve question 7

Scientists use significant figures to indicate the precision of a measurement. They help in communicating the uncertainty associated with a measured or calculated value.

Answer:

1. Energy is in the warmer water layers and in the interactions between warmer water and ice.
2. $1.1375$ g/ml
3. $1.0625$ g/ml
4. The warmer salt - water will sink because it is more dense ($1.1375$ g/ml compared to $1.0625$ g/ml of the colder fresh - water).
5. Warmer water moves towards the glacier due to density differences, which is a characteristic of convection.
6. A berm could block the flow of warmer water. It would be more important near the bottom as the deeper, warmer water is the main cause of glacier melting.
7. To indicate the precision of a measurement and communicate the uncertainty associated with a value.