Hey, I recognize that model of kindle! It’s the same as mine, a 4th gen non-touch. Have you ever thought of jailbreaking it to use koreader? I jailbroke mine and koreader is much nicer than the stock interface. Here is a good tutorial for this particular model (in comments, by spartanheavy): https://www.reddit.com/r/kindle/comments/1ipko3u/got_myself_kindle_4th_gen/
I haven’t needed to search for an amp myself since this is my only “good” pair of headphones, and they sound fine right out of my PC.
I looked into it, and I found this video from crinacle (well known audiophile in the headphone world) that discusses options that are in the ~$30 USD range that would definitely be loud enough. Namely, the JCALLY JM20 Max. In the video he does warn that this dac/amp could be too loud for some headphones, so maybe you could try the JCALLY JM6 Pro instead (~$15 USD). I would highly recommend watching his video to weigh your options.
The 250 ohm version probably needs a decent headphone amplifier to be loud enough, the 80 ohm version will work with any headphone jack you plug it into.
I have a pair of DT770 pros 80 ohm and they work with anything that has a headphone jack.
Let’s assume Costco size hot dogs (1/4 lb, or 0.11 kg), with an internal temp increase from fridge temperatures (37 F, or 276 K) to 165 F (347 K). Let’s also assume the heat capacity of the hot dog is about 3000 J/kg*K. To heat up a single hot dog takes this much energy:
q=mc*deltaT => q=(0.11 kg)*(3000 J/kg*K)*(347K-276K)=23,430 J of energy.
The heat capacity here is 9GW. That is 9 gigajoules of energy per second, or 9 billion joules every second. Divide this by the number of joules to cook each hot dog gets us the number of hot dogs that could be cooked every second:
9,000,000,000/23,430=384,123 hot dogs/second
With this hot dogs per second figure, we can find how long this energy source would take to feed the entire US population a Costco hot dog.
342,000,000 people/384,123 hot dogs per sec=890 seconds
Converting this to minutes:
890/60=14.8 minutes
So, this source of energy could feed the entire population of the US a Costco hot dog in less than 15 minutes if properly harnessed.