Explanation:
If you write it in English so I can help u if you need it
Answer:
Feathers are great thermal insulators.
Explanation:
Feathers are great thermal insulators. The loose structure of down feathers traps air.
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.
We can use the equation vf (the final velocity) =vi (the initial velocity) +at (aceleration times time)
We know the final velocity 100m/s, the initial velocity 0, and the acceleration (gravity) 9.8m/s^2. So, 100=0+9.8t. t=100/9.8
A sample of nitrogen gas has a volume of 5.0 ml at a pressure of 1.50 atm. what is the pressure exerted by the gas if the volume increases to 30.0 ml, at constant temperature is 0.25atm.
On constant temperature, the pressure and volume relation become constant before and after the change in quantitities have occurred.
According to Boyle's Law,
P₁V₁ = P₂V₂
where, P₁ is pressure exerted by the gas initially
V₁ is the volume of gas initially
P₂ is pressure exerted by the gas finally
V₂ is the volume of gas finally
Given,
P₁ = 1.5 atm
V₁ = 5 ml
V₂ = 30 ml
P₂ =?
On substituting the given values in the above equation:
P₁V₁ = P₂V₂
1.5 atm × 5 ml = P₂ × 30 ml
P₂ = 0.25 atm
Hence, pressure exerted by the gas is 0.25atm.
Learn more about Boyle's Law here, brainly.com/question/1437490
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