Strategies to Help You Through PADI IDC Physics Exam

In all the years I have been involved in PADI Open Water Scuba Instructor IDCs, the Physics exam is by far the most common “stress causer” that affects IDC candidates. Sadly often, it is the mere thought of doing Physics, even just the word that deters some candidates more so than their ability to answer the question.

Often, when getting a question wrong the candidate will reply, “ I knew that, I don’t know why I didn’t do it”. A candidate could do that multiple times on an exam. The more times a student does that the more pressure builds for the next exam.

The good news is that PADI does not expect you to be a physics professor. They just want you to have a general knowledge of physics and apply it to scuba diving. They would like you to understand the cause and effect.

Some of the questions in the instructor exams are not that difficult. Some buoyancy questions can be no more than a division and a subtraction. It is no more difficult mathematics that we would do in day to day life.

Often it is not the complexity of the mathematics, it is more the state of mind of the candidate that gets in the way.

As you will see these strategies do not tell you how to answer the questions, they try to help you prepare for an exam and understand some of the topics involved in physics and scuba diving.

1. Think the question through

Most candidates get tied up with the mathematics of the question rather than what the question is asking.

Often when counseling candidates on the why they got the question wrong, the issue was that they went straight into answering the question, rather than understanding what the question is asking.

Take the time to work out what the question is asking. You can’t answer a question before you truly understand what the question is about.

One good way to understand a question is to place it into a practical application to everyday scuba diving. Most of the questions can relate to things that occur every time you dive. You just to find the likeness. For example, buoyancy and displacement is what allows a person to float on water. A lot of students elect to do the float when doing their PADI Open Water water skills. Partial pressure increase, density, increased air consumption also occur every time we dive.

If you can’t make a connection then ask you PADI Course Director for one. It is vital you understand what is going on before you can answer the question.

BIG TIP: Understand what is happening with the question before learning the mathematics of answering the question.

2. Draw the picture

I have either taught or done literally 1000’s of physics questions over the years. Virtually all of them I have drawn a picture. Not a little scribble, a full-page diagram with all of the possible details I can. This helps me visualize the answer before I start.

Of all of the tips I will give I think that this is one of the most important. It helps you understand the question and guides you to an approximate answer.

For example: The exams are littered with pressure and flexible container (balloon) questions. I draw different size balloons according to depth. I then know approximately what the size of the balloon should be which leads to the next tip.

3. Eliminate obvious wrong answer

Statistics and probabilities are wonderful things. All PADI I.E exams are multiple-choice and you have four answers to choose from. You have a one in four chance of getting the question correct.

What this means is, theoretically the law of averages would say that even if you knew nothing about Physics (or any other topic for that matter) and you guessed every question, the minimum you should get is 25%.

A lot of the PADI questions have one and more often two questions that are clearly wrong and easy eliminated. By understanding the question and drawing a picture, this becomes a much easier task. If you eliminate two of the answers you now have a 50% chance of getting the question correct.

So now, let us say you do know 60% of the physics (we would hope you do before I.E day) and you were able to eliminate two of the four answers of the remaining questions. You would have a 50% chance of getting those correct (20%) and you add that the 60% you do know and BAM! You have passed the exam.

What eliminating incorrect answers does is allows you to focus on the possible correct answers, which in turn makes your calculations a lot easier.

For the record, the most common reason candidates get questions incorrect is failing to convert kilograms to litres or visa versa or doing the question for saltwater instead of freshwater or visa versa. The later is usually reading the question incorrectly. Make sure you FW or SW is clearly marked on your diagram as well as litres or Kilograms.

4. Get the answers you know out of the way first

This is not a tip for physics exams but for any exam you do.

The PADI Instructor exams as with a lot of exams are timed. You will have 90 minutes to do the Standards exam which is 50 questions and 90 minutes to do the Theory exams which are 5 x 12 question exams.

A technique that I use is to go through the and do just the questions I know I will get correct. I will leave the ones I am not sure about and will mark them so I can return to them easily. Then what I do is go through the ones that cause me a little thinking and leave the difficult ones. Lastly, I come to the difficult ones and use the rest of my exam time to complete them.

Let’s isolate the Physics exam as an example. You have 90 minutes to five exams. That means you have 18 minutes for each of the five theory exams including the physics exam. Each exam has 12 questions and that means you have 1.5 minutes or 90 seconds per question. It does not sound like much but it is a good amount of time. If you stew over one question for 10 minutes it means you have 8 minutes left to answer 11 questions and that is about 44 seconds a question. You have blown half your allocated time on one question.

Some of the questions that you answer in the exam may only take you as long as it takes you to read the question and the possible answers. You will know the answer immediately. Other questions may require to do some calculation and may take a bit longer.

Often I see students getting hooked up on one question which takes away time from the other questions. There are some bad mindsets that come with getting hooked on a question too long. Not knowing how to answer a question can cause stress and that can affect the rest of the exam.

If you go through the exam and only answer the questions you know first, you may find that you have answered enough the pass the exam anyway. This can also provide tips in answering the question you are having trouble. All this placed you in a better mindset to complete the more difficult question. It clears the mind so to speak

This technique will make your exam a lot easier and should take a bit of stress out of doing exams in general.