What am I doing wrong?

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OrganicChemist7

SN2 - Size Does Matter
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I have been following a similar schedule to SN2ed...and I am very frustrated with Physics.

I seem to not have as big of a problem with Chemistry, but for Physics and sometimes Bio I read the passage in BR and am dumbfounded.

Here is an example: I just completed Section 3 of the BR Physics book. I got every problem right in the chapter, and not taking very long to do them. I start the practice section, I get a few wrong. Ok.

I start the dam question (Passage I) and I literally have no idea how to even start it.

What am I missing here?

I am on Day 14/100.

Thanks.
 
I have been following a similar schedule to SN2ed...and I am very frustrated with Physics.

I seem to not have as big of a problem with Chemistry, but for Physics and sometimes Bio I read the passage in BR and am dumbfounded.

Here is an example: I just completed Section 3 of the BR Physics book. I got every problem right in the chapter, and not taking very long to do them. I start the practice section, I get a few wrong. Ok.

I start the dam question (Passage I) and I literally have no idea how to even start it.

What am I missing here?

I am on Day 14/100.

Thanks.

The text promotes a basic conceptual understanding of the material, which it sounds like you have given that you're getting the problems in the text correct. That's a good start. The passages intergrate other concepts (often from other sections) and they have some oddly worded questions that are fundamentally simple once translated (this simulates the MCAT experience). Getting used to those types of questions is also part of the preparation process, so try to not get so flustered. You'll get better by the end of the practice exams in each chapter.

The dam passage is challenging. It also has some extraneous information on magnetic fields in the passage that is designed to intimidate you. If the passage is overwhelming, treat the questions as free-standing questions and see how you do.

Question 1 is asking for the ratio of KE/initial PEgravitational.
Question 2 is asking for the setup in calculating energy given 20% efficiency.
Question 3 is on the theory that explains where energy is lost in the conversion process.
Question 4 is asking for an overview of the energy conversion process.
Question 5 is asking for an understanding of the device and how to improve it, which seems to be the hardest question and the one that requires understanding the passage.

I hope this helps somewhat. I know it's nerve-racking, but that is part of your preparation.
 
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I have the newest edition of all of TBR textbooks. I actually have the entire TPRH set, TBR set, EK set, 1001 set.

I started the passage and I couldn't get the first two questions which were more equation based. I memorized the equations but I sometimes don't know when to use them. The next three questions (3-5) were conceptual, not math based, and I got them all right.
 
The passages intergrate other concepts (often from other sections) and they have some oddly worded questions that are fundamentally simple once translated (this simulates the MCAT experience). Getting used to those types of questions is also part of the preparation process, so try to not get so flustered.

It also has some extraneous information on magnetic fields in the passage that is designed to intimidate you.

I know it's nerve-racking, but that is part of your preparation.

All of the statements above are why I 😍 TBR so much. Last year, I was SO flustered by the extra information in passages that I observed. I had difficulty differentiating what I needed to care about and what actually was important. Learn to not be intimidated (TBR helps me with that), and you'll be fine.
 
...I couldn't get the first two questions which were more equation based. I memorized the equations but I sometimes don't know when to use them.

That is such a powerful thing to know about yourself. It is a problem that can be corrected with practice, so you are in good shape. Some people work well by finding the appropriate equation based on what they give you while others find the right equation by what they don't give you.

In question 1, they ask "what percent of the potential energy at the top of the dam is converted into kinetic energy at the bottom of the dam?" They give you speed in the question. There are several types of potential energy, so from the passage we must infer that it's gravitational potential energy as they talk about harnessing the energy of falling water. That equation is PE = mgh. They also give you the horizontal speed of the water at the base of the dam. All that matters is the speed, because the "horizontal" term is irrelevent. The equation for the kinetic energy of a moving object is KE = 0.5mv^2. They want the percent of PE converted into KE, so we need to place KE over PE and solve. 0.5mv^2/mgh allows us to ignore the mass and take a ratio of gh/0.5v^2. The speed is 47.2 m/s and g is 9.8, so we can approximate it as 0.5(50x50)/(10)(150) which will lead to a value slightly larger than what they want. This is where we can cancel some numbers to help make the math easier.

0.5(50x50)/(10)(150) = (25x50)/(10x150) = (25x1)/(10x3) = 25/30 = 5/6 = 0.833​

83.3% is a little too high, so choice C looks tempting because it's the closest value to 83.3% while still be lower than it. The equations in this question were the usual suspects.

In question 2, they are asking for a fraction of the gravitational potential energy, so we need a fraction x mgh. What might help you on questions like this would be placing the units next to each term and seeing which combination of units cancels out to the correct final units.

The next three questions (3-5) were conceptual, not math based, and I got them all right.

This is excellent news, because those are usually considered the more difficult questions. Those are harder to perfect for most people.
 
I am also using the newest BR books and really struggling through the gen chem chapter 1 passages. I recently started the sn2ed schedule. Really worried about how to better my analysis of BR passages. I know the explanations will be helpful, but I understood the in chapter material. The passages just seem very dense and time consuming to understand. Do we even have that kind of time on the real test for reading dense passages? I am hoping that i get ALOT better in the next month.
 
Thank you for the words of inspiration. I have to say that since I joined this forum a few months ago I have gained such as valuable support system.

I will try not to get flustered and get rid of extraneous information. Thank you so much for the in depth analysis of the problem.
 
And just remember the passages are supposed to be confusing. I remember being frustrated when trying to answer questions about an astronaut in space only to realize later on that it was more simple than I thought.
 
Don't let that first chapter get you down Dr. D. I struggled on the first chapter in BR chemistry, cursing its existance. By the third chapter, I was loving the way they teach you something, ask it in a twisted way, and then show you it's a simple question. Despite the pain of the first few sections, I feel like I've gotten better at thinking my way through questions. I'm almost finished the first book for each subject. By the second book, I'm sure I will be on top of my game. I try questions from EK and TPR to test myself and make sure it's not just BR teaching me how to do BR questions, I breeze through them. I'm a little worried that EK is teaching me how to do well on EK passages, because their strategies don't work so well on TPR passages.
 
Don't let that first chapter get you down Dr. D. I struggled on the first chapter in BR chemistry, cursing its existance. By the third chapter, I was loving the way they teach you something, ask it in a twisted way, and then show you it's a simple question. Despite the pain of the first few sections, I feel like I've gotten better at thinking my way through questions.

I agree. It's like in the original Karate Kid, when Mr. Miyagi schools Daniel. "Wax on, wax off". Daniel had no idea what he was doing, but it applied later. And Daniel aced the MCAT.

Then Ralph Macchio got schooled by Dancing with the Stars.

Lesson of the day: It only works for the MCAT. Don't try applying it to the GMAT.
 
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