Aamc #9 ps (32-33)

[480225]

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I'm a little confused at the reasoning given for the answers to these two problems (I got both wrong and would like to correct the flaws in my reasoning). Can anyone explain them to me?

#32 Asks for an explanation of blue color (I don't think I'm supposed to post the full question, can edit if necessary)
- Answer provided is UV radiation is absorbed by molecules that then fluoresce at yet longer wavelengths.

- I siad that they would fluoresce at shorter wavelengths which they addressed by saying that this response doesn't conserve energy. (I'd like a formulaic explanation if possible, I understand now (and did then) that shorter wavelength = higher energy)

#33 Asks about compression of hot vapor bubbles
- The answer was that the process occurred to rapidly for heat loss as a result of rapid processes being adiabatic, but also addressed that answers such as "the surrounding liquid is subjected to the same compressional force" lack physical sense. Can anyone explain why it does?

Cheers.

 

[sciencebooks]

I'm a little confused at the reasoning given for the answers to these two problems (I got both wrong and would like to correct the flaws in my reasoning). Can anyone explain them to me?

#32 Asks for an explanation of blue color (I don't think I'm supposed to post the full question, can edit if necessary)
- Answer provided is UV radiation is absorbed by molecules that then fluoresce at yet longer wavelengths.

- I siad that they would fluoresce at shorter wavelengths which they addressed by saying that this response doesn't conserve energy. (I'd like a formulaic explanation if possible, I understand now (and did then) that shorter wavelength = higher energy)

#33 Asks about compression of hot vapor bubbles
- The answer was that the process occurred to rapidly for heat loss as a result of rapid processes being adiabatic, but also addressed that answers such as "the surrounding liquid is subjected to the same compressional force" lack physical sense. Can anyone explain why it does?

Cheers.

Forgive me as I'm just going off of your descriptions.

#32: UV is higher energy, shorter wavelength than blue... So if it's appearing blue it must have gone to a higher wavelength, lower energy.

#33: I think I'm missing the context to say, lol.

 

[Jepstein30]

I'm a little confused at the reasoning given for the answers to these two problems (I got both wrong and would like to correct the flaws in my reasoning). Can anyone explain them to me?

#32 Asks for an explanation of blue color (I don't think I'm supposed to post the full question, can edit if necessary)
- Answer provided is UV radiation is absorbed by molecules that then fluoresce at yet longer wavelengths.

- I siad that they would fluoresce at shorter wavelengths which they addressed by saying that this response doesn't conserve energy. (I'd like a formulaic explanation if possible, I understand now (and did then) that shorter wavelength = higher energy)

#33 Asks about compression of hot vapor bubbles
- The answer was that the process occurred to rapidly for heat loss as a result of rapid processes being adiabatic, but also addressed that answers such as "the surrounding liquid is subjected to the same compressional force" lack physical sense. Can anyone explain why it does?

Cheers.

If they absorb UV light and emit blue light, that means they are emitting longer wavelengths because blue light > purple > UV.

As for second question, I got that right based on POE I'm pretty sure.. the passage stressed how rapid the process was if i remember correctly.

 

[480225]

So for #32,

Since UV is greater E --> greater V ---> greater wavelength (E=hv --> v=wavelength x f)

#33

There answer used a POE style and looking at the question now that's definitely what I should have done, but for some reason the other answer stuck out to me even though it "lacks physicals sense." I'd post the question, but I'm not sure if I'm supposed to as it is AAMC material.

 

[Singhp03]

I'm a little confused at the reasoning given for the answers to these two problems (I got both wrong and would like to correct the flaws in my reasoning). Can anyone explain them to me?

#32 Asks for an explanation of blue color (I don't think I'm supposed to post the full question, can edit if necessary)
- Answer provided is UV radiation is absorbed by molecules that then fluoresce at yet longer wavelengths.

- I siad that they would fluoresce at shorter wavelengths which they addressed by saying that this response doesn't conserve energy. (I'd like a formulaic explanation if possible, I understand now (and did then) that shorter wavelength = higher energy)

#33 Asks about compression of hot vapor bubbles
- The answer was that the process occurred to rapidly for heat loss as a result of rapid processes being adiabatic, but also addressed that answers such as "the surrounding liquid is subjected to the same compressional force" lack physical sense. Can anyone explain why it does?

Cheers.

#32 answer makes sense
E= hc/wavelength (and as u said, longer wavelength is same as lower energy)

so the question ask for why a cell absorbs UV energy and projects blue(energy lower than UV)?--> some of the energy would have dissipated as heat or work and thus follows law of thermodynamics in saying E=q+(-pv)

Your explanation says, as the cell absorbs UV energy, it turns around and releases even more energy. This is in error with 1st law of Thermo, energy can't be created nor can it be recycled 100%, there is always some energy lost in an unusable way, thus the resulting wavelength must be longer, or reduced in energy, than the incoming UV energy.

#32 (IDK lol)

 

[Temperature101]

So for #32,

Since UV is greater E --> greater V ---> greater wavelength (E=hv --> v=wavelength x f)

#33

There answer used a POE style and looking at the question now that's definitely what I should have done, but for some reason the other answer stuck out to me even though it "lacks physicals sense." I'd post the question, but I'm not sure if I'm supposed to as it is AAMC material.

Shorter wavelength....E = hf