As is suggested by its alternative names (Physics Problems Q&A, Physics Q&A Exchange), the purpose of the site is to enable users to post and answer problem-solving physics questions. In particular it is targeted at the "homework-like" questions which are usually closed very quickly on Physics Stack Exchange - ie those which describe a specific situation and require you to make a calculation or apply physical reasoning to deduce an answer.
Suitable questions are not automatically migrated here from Physics Stack Exchange, and this site has no official links with nor approval from Physics SE.
This is not intended to be a site for learning physics. Questions asking for explanation of physical concepts (What is a Black Hole? How does Surface Tension work? Which physical quantities depend on frame of reference?) are officially off topic here, as also are questions asking for discussion of ideas and engineering proposals (What would happen if....? Is this a good way of explaining the Photoelectric Effect? Would this plan to reduce global warming work?).
The focus is exclusively on physics problems - classwork, homework, multiple choice tests, exam preparation, etc. The problem can ask for a calculation (eg Calculating entropy) or the application of physical reasoning (eg How many images are formed by this lens? and What happens if AC is fed into a dynamo?).
There is no minimum or maximum level of difficulty for questions. Questions will not be closed because they are "too easy." Judging from interest so far, typical questions are at the pre-university or early undergraduate level.
Although some effort is expected to be shown - like Physics SE, we do not do your homework for you - we try not to close questions because of "lack of effort". We prefer to point out mistakes, explain difficulties, and help you finish the question yourself if possible.
The format is very similar to Physics Stack Exchange. Each question allows multiple answers. Each answer should present a solution to the problem (either complete or in outline), so you do not need to scan through a discussion (as on Physics Forums) to find the answer. There are comments and voting, a reputation system to identify and reward frequent contributors of good quality questions and answers, and flagging of material which is thought to breach site policies.
There is a Meta Site to discuss the operation of the site and to formulate and vote on policies. The current site policies can be found in the Meta posts Scope and Guidelines and Close Reasons.
The main differences with Physics SE are (1) we focus exclusively on problem-solving ("homework-like") questions, and (2) we aim to be much more tolerant and to close questions only as a last resort.
 This question could be acceptable in a multiple-choice format.