<span>A: put an atom on a poster in the exhibit
Good luck. The poster itself is made of trillions of trillions of trillions
of atoms. You could not see the extra one any easier than you could
see the ones that are already there, and even if you could, it would be
lost in the crowd.
B: use a life size drawing of an atom
Good luck. Nobody has ever seen an atom. Atoms are too small
to see. That's a big part of the reason that nobody knew they exist
until less than 200 years ago.
D: set up a microscope so that visitors can view atoms
Good luck. Atoms are way too small to see with a microscope.
</span><span><span>C: Display a large three dimensional model of an atom.
</span> </span>Finally ! A suggestion that makes sense.
If something is too big or too small to see, show a model of it
that's just the right size to see.
Answer:
v ’= 21.44 m / s
Explanation:
This is a doppler effect exercise that changes the frequency of the sound due to the relative movement of the source and the observer, the expression that describes the phenomenon for body approaching s
f ’= f (v + v₀) / (v-
)
where it goes is the speed of sound 343 m / s, v_{s} the speed of the source v or the speed of the observer
in this exercise both the source and the observer are moving, we will assume that both have the same speed,
v₀ = v_{s} = v ’
we substitute
f ’= f (v + v’) / (v - v ’)
f ’/ f (v-v’) = v + v ’
v (f ’/ f -1) = v’ (1 + f ’/ f)
v ’= (f’ / f-1) / (1 + f ’/ f) v
v ’= (f’-f) / (f + f’) v
let's calculate
v ’= (3400 -3000) / (3000 +3400) 343
v ’= 400/6400 343
v ’= 21.44 m / s
Answer:
A High-to-Low
Explanation:
its like water running down a hill.
Answer:
D. is greater for turbulent flow than for laminar flow
Explanation:
what is friction drag?
- friction drag is a phenomenon experienced when a body moves through a fluid. A practical example can be seen in the mild warmth we experience rubbing the palm's of one's hand together only in this case we are dealing with a solid body and a fluid (e.g air, water). friction drag is directly proportional to the area of the surface in contact with the fluid and increases as velocity increases. We see a practical example of this when the rate at which one rubs the palms together is fast but we use the word turbulent when we are dealing with fluids. Turbulent flow creates more friction drag than laminar flow( Flow between a smooth body and fluid) due to its greater interaction with the surface of the body
- it is important to know that friction is also called viscous drag or skin drag
- I recommend Richardson and coulson vol 2 textbook, page 149, Chemical enginering fluid mechanics textbook by Ron dardy, page 341 for clearer explanation