With the grass example, I could see how it can be easy to have come up with that estimation if you were in a place that had grass. how can you make estimations if you aren't in a setting that allows you to take some basic measurements that might be needed to increase the accuracy of your estimation.
Why do physicists feel the need to use this back-of-the-envelope method that only gives an estimate instead of calculating a more accurate and reliable answer in cases where its possible to do so?
Must we have a personal experience to accompany every assumption or can we just state information we already know?
How can you develop skills to estimate, when for certain situations so many variables contribute to what you are estimating
How realistic will our explanations of our assumptions have to be, especially when we get to topics that we may never have visualized?
When we try to estimate something how can we determine the types of dimensions we will need and what equation we will use?
How useful is street mathematics in physics because if we want to discern basic principles of physics why is it useful to use estimates instead of more accurate values? if estimates can be so off how are we really discerning something about physics when there is such a large error bar?
How can we determine how many significant figure of precision is adequate for the problem we are solving?
Why is it appropriate to estimate only with linear dimensions rather than mass, volume, or area? For example, if estimating while baking, would it not be more practical to estimate that you've measured approximately one cup of flour rather than an approximate 3 inch diameter cylinder?
What would be the most crucial set of biological numbers you think we should know for this course? I know you gave a list of that website, but that would be quite difficult to try and memorize all of them.
How would one use the Fermi method in order to estimate the number of bacteria within a colony? I recently was asked this within my microbiology class, what I know is that a colony was about 25uM and a bacteria cell is about 1-2uM. The professor told us that is was 10^9 bacteria. How would I also reach this conclusion?
I actually do this sometimes but not as intricately as you have described obviously but what dictates whether an estimation is plausible or valid or not?

How do we know how loose we can be with our mathematical model when estimating a quanitty? For example, how should we know that treating tomatoes as cubes will be accurate enough (given that tomatoes don't stack neatly like cubes, so they won't fill a container like cubes) instead of estimating tomato volume based on a spherical shape?
How are we going to acquire the skill of estimation? How would we know to say that our thumb measures
10 blades of grass per centimeter? Will we do problems like these in recitation?
Equations in physics often involve a lot of math - how can we be sure we are calculating things precisely if we are only using estimations instead of actual values?
Can you ever make broad assumptions when doing estimations or must you always start with very specific assumptions and work up to the thing being estimated like in the grass example
When it comes to exams, will we see questions similar to the blades of grass example described in the reading? Additionally, are we expected to memorize the benchmark numbers provided on the Harvard website?
Why should estimation matter if most of the problems we do in school and in the outside world need exact values? I understand it is useful to have an estimate in your head, but you would then still need to calculate the actual value.
When you're solving an estimation problem, how close is reasonably close? I'm not sure I would even know where to begin when attempting to estimate how much leather a herd of ten thousand cow could yield.
If we use back of the envelope calculations, how certain can we be that the calculations closely resemble the actual answers. Also, how do we account for errors in the variation of body measurements (thumbs) from person to person?
What kind of basic measurements should we learn to approximate?
How important is rounding for more numerical problems? Does estimation and rounding for simplification go hand in hand or are they separate practices?
How is it possible to estimate something at a microscopic level with just using the naked eye? How can personal experience extend to such small sizes in measurement?
How can you decide when to use estimation rather than needing to find the precise measurement of something?
By relying on human observation to make estimations, would there not be a huge amount of error in the estimations? Most estimations would be based on things we see everyday and not things we actually focused on. We would be recalling from brief memories which are shown to have a lot of bias and inaccuracy since memories are reconstructed when recalled.

What is the point in estimation when we can just get an exact answer using a calculator? Estimation does not seem practical.
Why do we never practice estimation in our classes if they are so applicable to real life situations?
How will we be able to use personal experiences to estimate things that are not visible such as atoms and molecules?
When estimating, how does one know whether his or her estimate is accurate enough to be considered valid or incorrect? What is the cutoff between a close estimate to the real value and a wrong answer? If I attempt to estimate the number of blades of grass in a square meter in an average lawn, is there a point where my answer is too far from the real one to be considered an estimate? If so, how do I define it?
Estimation should be using a physical principle and then using that value to estimate a certain area/volume etc. What determines a good physical principle. I know you used the example of the thumb, but are there such things as "bad" physical principles and how do we go about determining which ones we should/should not use in an estimation scenario.
I understood the example in the reading about estimating the grass. However, if we were to be asked a question about how long a strand of hair would grow in 3 months, how would we go about answering that because we are estimating for the future and don't have much information in the present to use?
Are the useful numbers something we need to memorize? Since humans cells can vary in size, should we know the major differences in certain cell size?
What is the value in estimation? In most academic classes, accuracy is valued over anything else. If you had to do a math problem and you do not have the same answer as your professor, then you get the problem wrong. However, no two estimations will be guaranteed to be the same.So why then is estimation such a valuable component of physics? Isn't it important to have an exact, and as accurate as possible, answer?
Are Fermi Problems all solved using the factor-label method that was used in Honors Physics high school classes? Or, can you solve a Fermi Problem using estimations in many different equations?
For the purposes of an exam, would we get a sheet of reference numbers that we might need (examples may include the size of an average human thumb, or the size of an average blade of grass), or are we expected to memorize every number you gave us on the "useful numbers" page?
When do we use estimation relevant to biology in real life
What if we don't have a personal experience to relate to a problem that is asking for an estimation? How else can we approach the problem?
When using estimation, is there such a thing as only one right answer?

With various programs, such as Image J and MatLab, becoming increasingly common as a tool to quickly quantify data, what benefit does estimation have over the ability of these tools to give us data quickly and effectively?
I still do not really understand the point of a scientific estimation. If these estimations are potentially flawed, why not simply determine the exact answer to the problem? In other words, when would an estimation be practical?
Is the ability to estimate a better skill to have as part of math in science more than math in math? From experience, it was always better to be accurate with math in math rather than making estimations when solving a given problem.
I have only ever used estimation in biology for ecology/population ("we caught 13 grasshoppers in this area so there must be 52 in the whole field"), so what else is it most commonly used for? And is there any use for estimation in medical practice?
Is there any situation where an estimation might actually be more accurate to describe something in the real world that is flexible/changing rather than a hard calculation based on established numbers?
Directed towards a doctor, what percent of his emergency room care involves estimation? (I would assume a fair amount, and feel that it would be interesting to get his perspective on how estimation is used in high pressure, medical care situations)
In the reading it gives the blades of grass example, that would receive full credit that includes a plausible personal experience. If we come across a problem where we either cannot recall or have no personal experience to reference, is there any other way to gain full credit? Or if we come up with a plausible experience we have not actually had in real life, but our estimation is off, like if someone had estimated
30 blades of grass rather than 10 were able to fit in a length similar to the last joint of their thumb, would points be marked off?
What is the best way to develop my numerical estimation skills?
How can we estimate measurements for larger scales, if it is difficult to relate it to a personal experience? for example, if we are asked to estimate the distance from earth to mars, how should we start? should we memorize some distances (like for example from earth to sun or earth to moon) and just apply that?
How would you go about estimating linear dimensions and then going to get area and volume from that? would any estimation with plausible explanations receive full credit?
How do I develop the skill to quickly and accurately convert from one unit to another, for example square centimeters to square meters?

When it says to only use one to two significant figures in our calculations, and that we will lose credit for significant figures we have no information about, does that mean that all the constants that we will be given throughout the semester will only be given with just one to two significant figures as well?
If a certain estimation pertaining to an important idea in science, say an estimation involving the size of an atom was more precise, would this change everything and allow for more discoveries to be made or is it somewhat irrelevant?
In my previous science and math courses, we were always taught to find exact answers from our calculations. When we are asked on an exam to estimate, how are you grading the responses since answers can vary by how the student thought through the problem?
Not everyone has the same amount of experience - thus will we be given data that substitutes for our experiences in order to give good estimations?
Is the process of estimation helpful in every course? or is it just physics because of the math we're doing in this class more complicated than the math in pure math?
How long does it take to make an "acceptable estimation?" SInce our ability to estimate is limited to our knowledge of facts, if we do not have the necessary components to give a proper estimation, how then do we estimate without guessing?
Is it possible to make an accurate estimation without knowing all of the benchmark numbers?
Can we use any sort of reference to solve a problem even if it is not related to the question at hand but still makes logical sense?
Will we be required to memorize the useful numbers or will they be given to us on assignments/exams? if we are to use personal experience as a point of reference to estimate certain things, then what happens when students have different estimations of the same thing? Is there such thing as a right estimation?
Should estimation be used in problems/equations that call for exact solutions; if so, how do we as students incorporate this skill into more advanced physics problems?
In the reading, one of the advises regarding estimation stated that we shouldn't attempt more than one significant figure of precision. Does this statement still apply even if you are certain with more than one significant figure of your precision (for example, I know my exact height and this value has more than one significant figure)?
It was stated that "learning how to quantify and extend that personal experience is extremely powerful" in relation to Fermi's A-Bomb experience. However, how can one come up with a reasonable estimate if everyones preception of reality differs, who can we trust?

When doing estimation there is a large possibility that the equation used to get to the estimation can vary from person to person, all being plausible ways to estimate. But this may also lead to a difference in the estimate, with one estimate being a better representation than the other so what determines a good estimation?
How would you estimate/guess a mass from a linear dimension?
For area or volume you can use the length from the parameter, and then use a formula. But what about mass?
I can only think of using weight = mass*acceleration due to gravity (where isn't estimating weight, similar to estimating mass?
), or density where D=M/V, also not linear dimensions.
How is one able to make an educated assumption about a substance or quantity when little to no information is given about the subject being estimated?
Would we be able to estimate everyday phenomenon like Enrico Fermi by the end of the semester?
While creating our own calculations to do an estimation problem, does it not require a much higher level skill in mathematics? Or does the highest skill level of advanced calculus actually help create estimations
(almost) accurately?
What if I cannot relate any personal experience to an estimation problem? What if I have never had a meaningful experience with the concept that I am being asked to estimate?
As a scientist, if we're making "important" calculations why would we want to estimate? Even if our estimation skills get better and it ultimately helps us to save time wouldn't it be better to get an accurate number?
I've always been TERRIBLE with estimations. Distances in feet, time to get somewhere or number of major les to separate them, even the "jar of jellybeans" games - I'm always WAY off. How can I get better at estimations? Do I Just need to practice?
The article says "Knowing that the last joint of my thumb is about 1 inch long, I can easily imagine the grass against it. I can then see about 10 blades of grass against half that thumb joint, or 10 per cm. " How did we come to the conclusion of 10 per cm??
What are good ways for prompting good (relevant) personal experience reference numbers? Especially in situations of time restrictions, in which one may be frazzled and tempted to guess on things such as weight and area?
Are we going to be required to do calculations using the metric system? For example, I would know that my thumb is about 2 inches, but I would have to look up the conversion rate to cm, and that would require the use of my computer.
Is the "thumb" strategy a good method to approach estimation questions or is there other standards that students have used in the past?

When making estimations, there is of course a certain level of error. How are we to figure out what our margin of error is and how much that impacts the validity of our answer?
Is it necessary for students to memorize all the benchmark values listed? Will these values not be given to us when it is important for us to use them in the future?
While slightly off topic the term was mentioned in this section. Why are sig figs necessary/ relevant/ useful? They seem to be more of a bother than they are worth.
These types of questions are not graded by accuracy? What happens if one of your estimation in which you gather the rest of the problem's information is completely wrong?
For estimation problems on homework/exams, how much does accuracy matter? If we end up with a completely inaccurate number but are able to explain it with a sound process, would we get full credit?
Will we have to do these kinds of estimations in class
I saw them on the math pre-test and found them difficult.
How would the answer about estimating the amount of blades in a grass field change, if you were given the length and width of the grass field? Also, does the shape (hill/spherical or flat/rectangular) of the grass field matter?
Because a part of this estimation process is having prior knowledge, would different people be better at certain estimations than others because of their prior knowledge and education or background?
One of the pieces of advice state that "When dealing with areas or volumes of objects with complex shapes, idealize them as if they were some simpler shape, a cube or a sphere, for example." How would we go about choosing which simple shape to choose for an irregular shape such as Testudo? Could we choose either a cube or sphere as long as we justify and explain our assumptions?
I don't really understand how to relate personal experience to estimation. Is that the only way to accurately receive full credit? Because on a test there is no way I would be able to think of this type of relationship on the spot.
Is it good practice to use estimations as much as possible or should the practice be restricted to situations in which one does not have access to the tools or time necessary to take accurate measurements?
How accurate are the estimations of physicists when they apply them to real situations or use actual data? Did what the physicist who assumed a spherical cow have a useful impact on the dairy industry?
How will one know when it is appropriate to use estimation in a real-world situation?

You mentioned that the skill of quantitative estimation has many great benefits including being able to save time by deciding what matters and what doesn't? How would you would one be able to tell if something doesn't matter?
How accurately are you able to estimate most things? How much more inaccurate do estimations get as you use more numbers?
When would we need to use estimation techniques like this outside of physics? Are you giving a a certain type of estimation problems?
When we guess something to start an estimation, it might vary from person to person. How can we know who is right when sometimes the value can be somehow abstract or hard to specifically calculate?
On exams when you ask us to give estimations, will we be graded based on our reasoning for how we came up with our answer, no matter how off the actual answer is?
Will we learn all of the benchmark numbers needed to do biological estimations in class or will we need to do research on our own?
If an estimation problem comes up and i have no experience with it at all should i make up numbers in the most logical way possible?
Our generation has been spoiled by the availability of all kinds of technology and information, such as computers and internet. Very few of us ever do mental math as a result of calculator apps on everyone's smartphone and even in math classes in high school and college, professors allow students to use graphing calculators. When so much technology and information is readily available, what is the value in learning how to estimate? when it comes to estimation will we need to know certain equations to find the area, volume, or mass of a simple shapes, such as a cube or sphere?
How do we find the proper equation to represent real life occurrences? I don't see how a biologist can look at something and then derive an equation to represents that biological phenomenon.
If a problem involves estimation and you are estimating certain measurements based on your own experience, then wouldn't these estimations be different for everyone? Thus, there wouldn't be one right answer for that problem right?
When doing estimation problems, since experience is variable and answers are construed a variety of ways, is there a large range of answers that are plausible? Or is there a small ballpark of acceptable answers?

If we know some random fact (by chance, not by experience) can we use it? Also, if we dont have a experience we can relate to, how should we start the estimation process?
The estimation of the blades of grass example makes sense because one can easily imagine the amount of individual blades of grass against their thumb (that they measured before). However, when estimating much smaller things, such as numbers of papers within a book, I believe that the amount of error would be a lot higher. Should remember a measurement of something smaller and imagine pieces of paper against that, or should we still just imagine it against our thumbs?
If we make an assumption, can that assumption be considered wrong on an exam? for example, if you wanted us to estimate how much one's hair grows in a year, and I assume it grows an inch/minute. This is clearly wrong, but its my assumption for the problem.
How much does subjectivity come into play and affect our results/grades when using references to estimate a given quantity? For example in the reading it states "I can then see about 10 blades of grass against half that thumb joint" and based off that statement alone, if someone else say 15 or 20 blades then the final result would be vastly scaled up.
How proficient are we expected to be at estimating? For higher power estimation how close should we aim to estimate?
For the typical exam question, what if I do not remember any particular experiences that pertain to the question, for instance "I can then see about 10 blades of grass against half that thumb joint," what if I have never actually had that personal experience, then how do I get an estimate?
It seems like estimating is a slippery slope, you have to assume that one thing is true and then that will lead to your final answer being true, how accurate can your final answer be if you can't even make the first assumption, or if you do and its false?
How would you make an estimation when you do not have any background experience that relates to the estimate? For instance, in the piano tuner question how would you answer it if you did not personally have any experience with the piano or know no one who played it?
Do physicists typically use Ferni problems also as a method to double check their calculated values? For example, if a physicist makes an estimation and the calculated value is off by many magnitudes this could indicate an error in either one of their solutions (i.e. calculated or Ferni).
Will estimation problems be on exams, or will they just be something we practice with homework and other assignments to hone our skills? If they will be on exams, what will the criterion be for grading them, since they will not necessarily have a correct answer, or even a correct procedure to follow?
If the number derived for our estimation is wrong or not close to the actual answer of the given problem, would we still receive credit if the method we used for our estimation is sound?

How can I do my own numerical estimations if many are already made up?
The webpage says that quantitative estimation is really based on extending your personal experiences.
What if your experiences are misinformed or significantly different than the norm? As long as we explain our underlying assumptions, will we still get full credit on an estimation problem if our answer is slightly different than the key, but follows our assumptions?
If a scientist has little to no prior knowledge of the problems topic, then how can they make a close estimate?
Since you had indicated in the previous lecture that often times with math in science that nothing was exactly precise, would this imply that most of the calculations we do are in fact estimations
How far off can your estimation be and still be reasonable
In an estimation problem, should we always start with information from personal experience?
It says that there will be estimation on our tests and quizzes and such, and so, would that technically mean that on any given free response question on our exams, there is a possibility that multiple answers can be correct? On another point, since all things physics are technically impossible to calculate exactly, as you said earlier in class today, wouldn't that mean there is no actual precision in the real world, rather than on paper in which the numbers can show the number that we aim for, since the actual values will always be a little off?
It says not to calculate past two significant figures, but what if you feel you can accurately estimate, in your head, up to three or possibly more significant figures? Does that mean you can go past that for an estimation, if it is rooted in experience?
Say one tries to estimate based on personal experience, such as grass per square meter, but the estimation is still very inaccurate. Does this yield acceptable estimation?
How do I begin to develop the skills to estimate objects that I may not even be familiar with ?
Since estimations are so useful in everyday life why were we never taught how to properly estimate in previous math courses? I can think of many instances where knowing how to come up with a good estimation would have been beneficial.
Is it possible that situations can arise when estimation would limit our scope of the possibility of answers, when in actuality the answer is something else, and our presumptions led us astray?
What are the boundaries for estimation? How far or much can we estimate to still yield a reasonable conclusion?

When we determine an answer through estimation, what are some ways (logical, mathematical, etc.) that we can check to see how accurate our estimation is, beyond when our estimation is obviously too small or too big? If there aren't many ways to do that, is there a range of accuracy that you look for in our answers?