With hard work AND a great maths teacher, I went from a 60% 3U student in Year 11 to a 92% - 96% 3U student to Year 12 not only because I pushed myself but because my teacher has learnt that I learn pretty slow and goes through step by step (while letting all the 4U kids rush ahead without me).
At times, teachers DO have a role in your education.Without the care of my maths teacher and her specific catering + dedication to forcing me to show her answers I get wrong at lunch, I wouldn't be achieving the scores I am now. But if accounted with a bad teacher, it will only require MORE effort from the individual themselves to overcome that and work hard on their own. If you solely rely on a teacher, then yes, they did majorly contribute to your bad marks.
But I think most of us are smart enough to realise we can put on extra work into ourselves outside of school.
Writtenloveletters (without trying to attack you here)
Imagine your maths teacher was rendered useless and he/she just gave you a textbook and told you to do questions without any demonstration. How do you think you could survive with a teacher like this? Friends teaching you? A tutor? You self learning the content and asking your peers for help?
Consider this: at uni people say that the lecturer goes at a quick lightning pace that almost no one can keep up with and there is very limited help out there (I think the only way to get help is via peers). How do you think you could survive in this environment considering how intense it could be at uni? (I heard that work done in a year at high school is equivalent to work done in a week at uni)
At the end of the day, you can't have some1 there behind your back and disciplining you for every second of the day. You have to have that self motivation to do your job. If your maths teacher doesn't set you homework, then do you just not do homework (because you assume there's no homework) or do you just do it for your own benefit? That's something I think you need to consider. I even heard at uni, they make homework optional bc it's your own responsibility for your own learning. I know even my maths teacher rarely sets out homework (but if he does, he never checks it)
All I am saying is that you need to be responsible for your own learning no matter what undesirable circumstance (such as having a bad teacher) it is and that you need to stop relying on that one teacher and try to get help from friends (it will help them as well as you) and possibly other teachers or ex-students. I faced a situation like this in the past and was extremely angry at my teachers and accused them of "not being able to teach, hence I got bad grades" but realised, why couldn't of I had self learnt the content and get help from other students and other teachers?
I'm not trying to say "Oh teachers are so shit why are they working in our school. Our school principal please fire them for not being able to teach". I'm trying to say, you need to be responsible for our own learning when we have teachers who don't work in out favour. The difference between a "good teacher" and a "bad teacher" is that a good teacher accomodates our needs and wants easier but a "bad teacher" doesn't do it hence it is harder for us to do well and we have to seek alternative means in order to combat that. You get what I mean?
Also getting a bit off track, considering that you aren't the best at physics, have you tried to visualise concepts before answering questions?