What is the function of the phytoplankton in ocean ecosystems?

As a result, energy cannot be transmitted easily through down feathers. This means birds are insulated from cold air outside, plus their body heat doesn't escape easily either.

Human beings discovered that down feathers are good for insulation long ago. For example, documents from the 1600s show that Russian merchants sold “bird down" to the Dutch hundreds of years ago.

Today, down is used in all sorts of products, including coats, bedding, and sleeping bags, to help better insulate the user from cold weather. Down can be collected from many different types of birds, but most of today's supply comes from domestic geese.

If you have a down coat or comforter, is it all down? In the United States, laws require that products labeled “100 percent down" contain only down feathers.

If your product is labeled “down," it can contain a mixture of both down feathers and synthetic fibers. Not all down feathers are created equal, though.

Down insulation is rated on a measure called “fill power." The higher the fill power, the more the down insulates.

The highest fill-power rating — 1200 — goes to eiderdown, which comes from the Common Eider duck. Eiderdown tends to be expensive.

3 0

3 years ago

A battery does work on electric charges to bring them to a position of higher electric potential energy so that they can flow th

Ipatiy [6.2K]

(Missing question is: which of the following statements are true?)

a) A battery does work on electric charges to bring them to a position of higher electric potential energy so that they can flow through a circuit to a lower potential energy --> TRUE
That's true: the battery does the work to move the charges to one end of its terminal thus creating a potential difference between the two terminals. Then, when it is connected to the circuit, charges start to flow to the terminal at lower potential (through the circuit)

b) the potential difference between the terminals of a battery, when no current flows to an external circuit, is referred to as the terminal voltage --> FALSE
This is false: when no current flows, it is called e.m.f. (electromotive force)

c) the internal resistance of a battery decreases with decreasing temperature
--> TRUE
In fact, the dependence of a resistance with the temperature is:
 $R=R_0[1+\alpha (T-T_0)]$
with $\alpha$ being generally positive, therefore the value of the resistance is proportional to T, and when T decreases, R decreases as well.

d) a battery is a device that produces electricity by transforming chemical energy into electrical energy --> TRUE
That's true: a battery uses chemical reactions to create a potential difference between the two terminals that can be exploited to make charges flowing through a circuit.

7 0

3 years ago

What are used by organisms for long-term energy storage

kifflom [539]

Answer:

Fatty acids.

Explanation:

-Long term energy storage is stored in the form of triglycerides .

-They are efficient storing molecules. They are more efficient thatn glycogen(cabohydrates).

-Fatty acids are more calori dense hence them being ideal for long term energy storage.

4 0

3 years ago