When homework-and-exercises questions are voted off topic and put on hold then the OP should be directed to the Meta Question which offers a choice of alternative sites.
To put this proposal into effect, the notification box could be amended to read :
put on hold as off-topic by ...
If this question can be reworded to fit the rules in the help center, please edit the question. If you cannot do so, recommendations for alternative sites are given in My question was closed on Phys.SE. Can you recommend me another internet site where my question might be on-topic?
Originally I had thought of re-directing the OP to the offshoot site Physics Problems Q&A set up by heather and Mew, but this might give the impression of official approval of that site by the Stack Exchange community. See :
Physics Problem Solving Site
Ethics - Redirecting homework solution seeking questions to a website built for that purpose.
Most questions in this category are asking specifically for help in solving problems. Typically they include "Is this correct?", "What did I do wrong?", "How do I start?" or "What should I do next?" It is far from easy to turn such difficulties into a question of a conceptual nature which would be on topic here, whereas the question as it stands would probably be on topic at sites specifically set up for help with homework or problem-solving.
When a homework question is closed, the OP often either (i) asks for a recommendation of a website where the question might be suitable, or (ii) asks how the question can be edited to make it on topic, or (iii) argues that the question is not actually off topic. In the latter case the OP leaves the site having had a bad experience. Recommending where to get an answer will save effort in dealing with these 3 issues and increase the chances of the OP having a satisfactory experience of this site.
Please up-vote my question if you approve of my suggestion and would like to see it implemented, or down-vote if you disapprove.