Put it this way, you have screwed up your chance of getting your desired ATAR if you maintained the mentality you have screwed up and no matter how hard you try, there is no hope. Don't let how you do in 15% affect the rest 85% of your internal marks. There are still a LOT of opportunities for you to improve your internal rank.
The following are just some advice:
1)Stop panicking and be realistic-doing bad in one assessment for one subject is highly unlikely to wreck your chances of getting your desired ATAR
2)Learn from your mistakes and remember to read over the exam paper carefully-i.e. at least twice before you start doing the questions-it is ok to make mistakes, as long as you don't make the same mistake twice. Make sure you know why you have made mistakes in the EXAM you have done.
3) if there is anything you don't understand-ask your teacher-whether it is at the end of lesson, after school, before school-don't wait before it is too late. Make sure in the future you understand absolutely everything your teacher has taught you and is prescribed in the syllabus. Don't be shy
4)Study hard in the subject consistently, do the homework, complete assessment tasks to the BEST of your ability, make notes, practice past HSC questions under EXAM conditions, do text book questions, mark your answers, circle mistakes, repeat this process as many time as possible and with persistent effort-you will maximise your potential to get that band 6 you want.
5) You've got 6 weeks of summer holidays in which you can consolidate over the knowledge you learnt for physics and even study ahead to maximise your marks-it is never too late unless you think it is and you make it so.
My top 3 tips for preparing for physics assessments and exams:
1)Practical assessments-make sure you know reliability, validity, accuracy, sources of error, possible areas for improvement, independent/dependent/controlled variables, risk assessment for all the experiments you have done in class, make sure you can master basic science skills such as drawing line of best fit, drawing experimental set up accurately, using numbered points in writing a logical procedure, understand the requirements of the exam(I.e. how much time, how many parts) and allocate your time accordingly, make sure you understand the chemical principle/theory behind why you did each experiment
2)Theory assessments and exams-make sure you PERSONALLY write a set of summarised notes according to each dot point of the syllabus in a concise but detailed manner-make sure you include appropriate diagrams as well, after you wrote the notes, make sure to start practising questions and CHECKING YOUR ANSWERS in textbooks-ask your teacher for practice questions and make links between dotpoints and across modules to reinforce your understanding. Throughout the year, you should be progressively cutting down your notes as you store more things into your long term memory-revise regularly. Before your final trial exam-you should try to get your hands on as many preliminary exams as possible to practice-and look at the marking guidelines, remember to practice under EXAM CONDITIONS. Make sure when you make notes you are at least referring to 3 different sources to synthesise your information. (colour-code and use mind-maps to make your notes engaging and easy to remember). In your notes, don't neglect to include all your experiments and second-hand investigations.
3)For other types of assessments such as group presentations, individual research assignments, second-hand investigations-you should strive to always include a comprehensive bibliography that indicates you have sourced your information not only from websites, but from journals/books as well, you should understand how to evaluate accuracy/reliability/validity in relation to the sources of information you are using, like other types of assessment, pay close attention to the marking criteria and make sure you fulfil it as much as possible, make sure your information is comprehensive, non-repetitive and answers the verb of the question: i.e. discuss, evaluate, compare, contrast, assess, examine (so for that matter, memorise what the main verbs used in your exam questions means)
http://www.mathscience.com.au/student_resources.php-this is also a good link for some more practice on physics-attack the dot points that you are not confident in-under exam conditions and mark and evaluate your answers by comparing to the sample answer. Remember, keep a positive and focused mindset. Those who get the top ATARs don't just stop trying because they 'failed' an assessment task, they evaluate their mistakes and implement better studying strategies to achieve even greater results. By browsing through this forum, you will realise a lot of people shares the same anxiety as you, so you are not alone. Just keep working hard and you will maximise your chance of achieving your desired results at the end of the year-hope this helps and I wish you all the best for the rest of this year
One last tip: compete with yourself-not others, you should focus on YOUR OWN RESULTS and trying to IMPROVE to ACHIEVE YOUR OWN PERSONAL BESTS