Problem based on magentic effect of electric current

Can anyone please tell me where this problem is from? Has anyone solved this before?
Screenshot_20230528_213649_Drive

Thanks!

So you don’t want to know how to solve the problem, you want to know where it is from?

2 лайка

I was able to solve it. I want to know if anyone has seen similar problems or this one somewhere else, like in russian olympiads or kazakh olympiads etc.