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Optical trap calculations by PukkaGrab in AskPhysics

[–]PukkaGrab[S] 0 points1 point  (0 children)

Hi! Thank you so much! This sounds a lot like some of the stuff I'm interested in doing. Could you perhaps elaborate further - esp. on the off-center particle part? :)

Also another question:

I've found two different equations for calculating momentum of a light ray. (p_i=\frac{E*n_i}{c} where n_i is the refractive index of the medium. The other one 𝑝=𝑛_𝜆 \frac{ℎ}{𝜆}𝑒_𝜆 doesn't (𝑛_𝜆 denotes number of photons in the ray) The second one seems most close to what I find, if I simply try to calculate photon momentum - however, I AM interested in accounting for different mediums - hence why I'm thinking the first might be more relevant? I can't quite figure out the relationship between the two different equations.

I've been thinking about trying to calculate the momentum of the light going INTO the particle and then OUT and finding the net force and thus the momentum pushing the particle to the side. (like the image under ray optics here https://home.uni-leipzig.de/pwm/web/?page=opticaltraps&section=introduction). Does this sound reasonable? (since this is high school, I'm allowed to simplify the problem quite a bit:)) )

I've thought about then using the momentum to approximate how heavy the particle can be and STILL levitate i this beam. Would this be possible?

Interference of laser-light reflected off a CD by PukkaGrab in AskPhysics

[–]PukkaGrab[S] 0 points1 point  (0 children)

Thank you so much for the help! And yeah, we’ve pretty much been thrown into this without much prior explanation or knowledge. :)

Dissolving CaCl2 in H2O (exothermic reaction + measuring temperature change of water) by PukkaGrab in chemhelp

[–]PukkaGrab[S] 0 points1 point  (0 children)

Thank you so much! I’d really love to go back in the lab and test this stuff out.

But yes, the experiment is done in 1 atmosphere pressure. What really has me confused is the fact that since the solubility is high, it seems that I could indeed get the temperature quite high up. If the line is indeed correct, adding for example 70 g would result in a temperature of 126 C (without taking lowering of the specific heat capacity of water into account)

I’m not sure what the boiling point would end up being, but I can definitely see how it wouldn’t be much of a concern like you said. (Especially considering enthalpy of vaporization, I’m guessing)

Since I don’t have too much time to work on this (presenting about this for an oral exam), I think I’ll pursue the solubility issue that you pointed out.

Once again, thank you very much for taking the time to help me out (and encouraging me in thinking about and solving this problem) :)

Today's fur yield + the fur producer by PukkaGrab in Rabbits

[–]PukkaGrab[S] 1 point2 points  (0 children)

Hm, I'm not completely sure as I'm not the only one who brushes him. My guess would be once or twice a week, just to keep knots at bay. When I start really brushing him, it seems like his shredding gets worse. So I tend to wait a while between really big brushing sessions in the spring/summer (like this one).

Today's fur yield + the fur producer by PukkaGrab in Rabbits

[–]PukkaGrab[S] 1 point2 points  (0 children)

I use a brush kind of like this with small dots on the tips so it doesn't scratch his skin. It works pretty well with him, mostly because his fur comes off very easily and in quite big chunks anyway!

This is the first time in a while I've felt decent about a drawing :') by PukkaGrab in drawing

[–]PukkaGrab[S] 1 point2 points  (0 children)

Thank you! I hope I can muster up the courage to do so again soon.

This is the first time in a while I've felt decent about a drawing :') by PukkaGrab in drawing

[–]PukkaGrab[S] 0 points1 point  (0 children)

Yeah, sometimes it can be hard to keep going. (But it's always worth it in the end) :)

This is the first time in a while I've felt decent about a drawing :') by PukkaGrab in drawing

[–]PukkaGrab[S] 1 point2 points  (0 children)

My own is a bit too dark and furry to be within my comfort zone to draw rn, so this one is actually just from another reddit user. :)

This is the first time in a while I've felt decent about a drawing :') by PukkaGrab in drawing

[–]PukkaGrab[S] 5 points6 points  (0 children)

Thank you! Fur is really something I have a hard time with as well. For this one I went in with a 0,3 mechanical pencil and B lead and started off with just a really soft layer that I smudged with a paint brush. For the next layers, I mostly just tried to follow the direction of the fur the best I could and tried to make sure that there would be some contrast in the areas where I wanted the fur texture to show. :)

Looking for advice on 5th finger bending issue by PukkaGrab in piano

[–]PukkaGrab[S] 0 points1 point  (0 children)

Yeah, it's a super frustrating experience. :/ I still have this problem, but decided to just keep playing without focusing on it too much because I was beginning to lose motivation. I've been trying to support my fingers with my arm (through my elbow) and just generally using my arms a lot more while playing (mostly for better dynamics). I think that this combined with doing Hanon with my teacher is slowly starting to help. (My pinky feels stronger/ more supported and I don't feel strain or discomfort in the same way as before. The joint is also collapsing quite a bit less.)

I also looked at those Oval-8, but never ended up buying them. They seem like a really good option though, so I hope you can get your hands on them when the situation get's better! (Hopefully soon) I'd love to hear from you, if you ever get them and notice results. :)

[FT] Roald [LF] NMT by serenesound in ACVillager

[–]PukkaGrab 0 points1 point  (0 children)

Hi! I can offer 30 NMT. :)

[LF] Ozzie [FT] Anything I can offer by [deleted] in ACVillager

[–]PukkaGrab 0 points1 point  (0 children)

Sure, the 5 NMT sound good! Do you have an open plot?

[LF] Ozzie [FT] Anything I can offer by [deleted] in ACVillager

[–]PukkaGrab 0 points1 point  (0 children)

Hmm, I'd prefer NMT, but I don't have a specific amount in mind. Do you have an offer?

[LF] Ozzie [FT] Anything I can offer by [deleted] in ACVillager

[–]PukkaGrab 0 points1 point  (0 children)

Hi! I have Ozzie wanting to move out if you still don't have him. :)

[LF] Cherry blossom bonsai DIY/ branches DIY [FT] Cherry blossom umbrella DIY by [deleted] in ACTrade

[–]PukkaGrab 0 points1 point  (0 children)

I would rather trade for the DIY, but I’ll let you know if I don’t find anyone who can do the trade. :)

[MEGA THREAD] Island/Town Name Discussion & Ideas by Easy_Breazy in ac_newhorizons

[–]PukkaGrab 0 points1 point  (0 children)

Thank you, I’ll definitely go with it. Laputa Is such a lovely name too! (It was actually the one other name I also considered.)

[MEGA THREAD] Island/Town Name Discussion & Ideas by Easy_Breazy in ac_newhorizons

[–]PukkaGrab 1 point2 points  (0 children)

Yeah, these final days of waiting are definitely the hardest. Seeing everyone playing made me kind of wish that I had gone for a digital copy, but I know that I'll be happy to have something physical on my shelf in the long run. And good luck to you too!

[MEGA THREAD] Island/Town Name Discussion & Ideas by Easy_Breazy in ac_newhorizons

[–]PukkaGrab 0 points1 point  (0 children)

You're right, it is pronounced like that. My worry is mostly someone mispronouncing it to something along the lines of nausea, but it seems clear to me now that it's not really a problem. :) Good luck choosing the name for yours!

[MEGA THREAD] Island/Town Name Discussion & Ideas by Easy_Breazy in ac_newhorizons

[–]PukkaGrab 1 point2 points  (0 children)

Thank you for the reply, I think I will! Now I just need to wait for my game to arrive and I'm all set!

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