1- let's take block height 731248 for example, the hash of that block is 0000000000000000000932577f24607495a93060ff4823a7c6f4a2b9db9582ee.
my question is, what is the miner hashing all together that in the end he gets that block hash that is accepted by the network?
could you please write an example, on what hashes something, that is the result of the block hash? which is 0000000000000000000932577f24607495a93060ff4823a7c6f4a2b9db9582ee.
I know that the end hash-result should be starting with a lot of zeros, but i'm always wondering which value(s) the miner is hashing to get that end block hash result.
Simply put, miners take the previous block's hash and add a nonce to it in an attempt to get a hash that is less than the current difficulty (has a certain number of leading zeros), here is a very simple example.
let's assume the previous hash is (11) and the miner is attempting a hash that starts with 0
if you hash 11 on it's own you get
4fc82b26aecb47d2868c4efbe3581732a3e7cbcc6c2efb32062c08170a05eeb8
you can use this website for testing >
https://emn178.github.io/online-tools/sha256.htmlso now I'll keep trying different values along side 11 to get a hash that starts with one 0
if I try 11f, I get
d6e3de5312a21c5a8c29f52895a62b9e7fa95353f4010981596adb1690b5f830
if I try 11f1
cb1e69aba1490a72448f6b57b166c895f3a44923630e2f5a350abeef326e5f5b
if I try 11f11
7085ae82df1433fc5749566d361f0e39a546d720cba84543f673bb6b695e3fcd
I kept trying all the way till I got to
11f1111111111111111111111111111111
and that gave me this hash which should solve a block
0299db69978d6c6b8a9afa2c6e2b9b24ae52df368b6170fa84ca30ed00cd3157
because this is just 1 zero, it was very easy for me to do it manually in just about 20 hahses, now if you try to get a hash with 0 zeros, it will take a lot longer, 5 zeros will be even worse and so on so forth.
Of course, the value the hash includes many other things besides the prev block hash, but this is just me oversimplifying the matter.
2- What is a good mining speed nowadays to get a good-imaginable chance to hit a block? in peta/s if possible.
To feasibility mine bitcoin you need to have a good share of the total hashrate, so anything below EH worth means a somehow large fluctuation, you won't be making more money mining solo (except the pool fees), so it's not worth the fluctuation IMO.
3- Do you think 100 peta/s has a good chance to hit a block?
with 100% luck, you need 15 days to hit a block, so you could do so in 15 days, maybe 15 hours, and maybe 3 months, the question you should be asking yourself is "if I get an unlucky year whereby I only hit half the blocks I thought I would, can I survive?"
of course, if you measure this against infinity, it will be no different.
4- What you think, how much would 100 peta/s would cost to run in term of electricity?
It will depend on your power rate and the efficiency of your miners, 100ph= 10000th, if you use something like S19 with 30w/th, it means a total of 30*10000/1000=300Kwh, or 7,200Kwh daily, if you pay 10 cents per KwH you will pay $720 daily, if you mine with S9s at 90w/th, you will pay 2,160 daily.
And with no offense to you, mining far with the same of 100PH will need at least 2 million dollars investment and a ton of planning.