Lab Reports

all right welcome to your first video of conceptual physics hopefully there will be many of these video lessons to come just to give you the idea of why we’re doing these video lessons instead of doing a lesson in class it’s because I found that when I stand in front of the entire class and talk I’ll often take a lot longer than I need to to say what I need to say sometimes taking as much as 40 minutes and then when I’ll sit down and try to explain the same thing to the camera it makes me a lot more brief so I usually will only take about 10 to 15 minutes in fact I can’t even record a video that’s longer than 15 minutes so if it goes longer than that I have to make a second video or something like that so because of that these videos will always be relatively short I do need to cover a lot in some of the videos and so i might go rather quickly please remember that another advantage of a video is you can always pause it and go back and watch a section again or stop it and just kind of think about what i’m saying or stop it and maybe take some notes about what i just said or think about a question if you have a question you can also pull up an email or pull up neo and send me a message about that right away there’s no stupid questions and in fact you don’t have to worry about embarrassing yourself in front of the class you just send me an email and i’ll respond and nobody will know ok so a lot of advantages to these video lessons we’re going to do it quite a lot but we’ll do all the practice mostly in class where you can actually get help and you can talk to your peers about what you learned and go over things in that way ok so i hope this helps i hope it works please give me feedback on the videos by sending me a message on neo or by telling me in person if it’s not working for you please let me know and we’ll do our best to make it work ok so we’re going to be talking about lab reports today we did our first lab in class the human measurement lab and we’re going to need to write the lab report for that like will do for all lab reports and so I’m hoping you had your physics lab rubric looks like this and of course it looks like the thing that’s on the screen you know right there and so we’re going to go through that real quick and try to make sure that you get the best possible score notice that it is broken down into five different categories that you’re going to be assessed on and for each category there is a bunch of different scores that you can get you can get a six or a seven or an eight or a nine or a ten as you go across the rubric now obviously we want to be on the ten side of that and so in order to make sure that we’re on the ten side we’re going to be looking at just the 10 scores and trying to make sure that our lab report matches that there’s a lot of information on here and so I want you to know that for the first lab report we’re only going to be focusing on the essential question and background the procedure the data table and a part of analysis meaning that you actually drew your graph we’ll worry about the rest of the analysis section and the conclusion in class and mostly will focus on that for our next lab because there will be more for you to write in those portions okay but don’t worry about doing that tonight we’re just going to do the first half of the lab report okay so let’s flip over to my lab report your paper should look something like this at the very least it should have these sections and so at the top of the left hand side of the page you should have human measurement lab but there should be a part for background variables and procedure on the other side of the paper it should say data table and you should have your graph next to that and under that is space for analysis into space for conclusion please always make sure that you organize your paper exactly like this I know that it sounds really picky that I will mark you off tour not organize your paper organizing your paper like this but when I have to grade a hundred and forty of these in a all night if you take me one extra minute because of the way that you organized your paper you cost me two hours of time with my son and that makes me very sad okay so just please do me the favor of making sure you organize it correctly I will not give you a very good grade if you don’t so simple thing you can do to make sure you get a good grade on your lab report also it helps you make sure that you don’t forget anything okay I would take a moment if I were you and I would pause this video and i would go ahead and read through these sections so i’m gonna go ahead and show you the background real quick alright so here’s the background i would go ahead and pause it and read did you do it i hope you did it because if not that’s pretty embarrassing um basically the idea of the background is you’re going to tell us what was your essential question but before you tell us the essential question you’re going to tell us where did the essential question come from so usually will have a activity or a video or something like that that gave us the essential question or helped us to develop that essential question you’re going to describe that in a short paragraph so like I said in here we watched a video about athletes bodies and how they’ve changed over time and that made us think about how our body proportions compared to the rest of the class and that’s our essential question for this lab notice that I said in the background section our essential question is there’s no secrets in here people tell me what your essential question is okay make it very quick all right now if we flip back to our lab report rubric you’ll see that to get ten points on the essential question or background section your essential question has to be well defined in other words tell me what your essential question is and also that you have to include all background information which means you need to describe what we did to come up with that essential question okay so as long as you did that you get 10 points that’s probably the easiest section though I imagine you’ll probably be tempted to write very very very little on the background maybe just like a word say something like we watched a video that’s lame say more than that we need to practice being more descriptive with our language so try to write in paragraphs all the time and that usually means saying the same thing more or less multiple times I mean look at how I wrote this I didn’t put a lot of time into this but this is a pretty good example so it says in class we watched a video about how athletes bodies have changed over time and then I give an example so I say the video mentioned how athletes are getting taller for certain sports like swimming that might feel like saying the same thing twice but it’s actually just giving more detail and that’s how we write good paragraphs and it’s how we get to the point where we can write longer and longer essays and reports and stuff like that in college I at one point in time had to write a 90 page paper so you don’t do that without repeating yourself a little bit maybe you’ll have to do that one day too and we want to practice so next thing we want to list is the variables and we’ll get into more detail about how to write variables later but for right now just list two things that you measured I am going to say that I measured arm length and height but you might have measured different things depending on how you did this experiment and that’s totally okay alright next thing is the procedure alright so i want you to pause it again and read through that I hope you paused it otherwise again pretty lame actually fun fact you could almost copy what i did this time okay i just want to make sure that you get a good example so especially for the background you could write basically the same thing that I said and then for the procedure it’s going to be different because I didn’t do your experiment with you and you might have done it a little bit differently than me but still it’s a good example and if you’re struggling with what to write for each sentence go back to mine and write something really similar to what I wrote ah so just use it as a template don’t write it word for word the same I’ll obviously notice if that’s the case but please use it as an example that’s the idea alright so the procedure in this one says talks about what we do and it gives a lot of detail about how we measured it let’s go ahead and look at the rubric again so as far as procedures concerned it says to get ten points you have to describe the independent and dependent variables for this lab you just have to tell me what the two things you measured are later on we’re going to learn the difference between an independent and dependent variable and then you’ll have to tell me which ones which but that won’t happen until next lab you also need to do a diagram of the setup which I didn’t do but you have to so right next to the procedure you’re going to draw a picture of what you did that’s to help you very quickly remember what was going on is you flip through the lab reports in your notebook because there will be a lot of them by the end of the semester and so this one’s just going to be like a picture of you measuring something stick figures are totally okay you don’t have to be super artistic about this but make sure there’s a diagram on there for the full ten points and then lastly it says multiple trials are identified multiple trials means that you actually measured the same thing more than once so if your buddy Eduardo is the one that you’re measuring you really should measure Eduardo’s height two or three times because you’ll be surprised you might actually get totally different measurements each time and that’s because there’s just a little bit of random error everytime you measure something especially you know when you’re trying to measure their height like you can’t get this direct line from the meter stick that’s over here you know over to their height and so there’s a little bit of estimating going on right so you’re going to get a little bit different numbers because of that and in all of our further labs you want to do multiple trials or you will not get full credit notice if you don’t include multiple trials in your procedure you don’t get ten points you get six because that’s what the rubric says so that’s that’s bad okay alright let’s move on to the very last thing we’re going to talk about I have four more minutes in my video and so that’s going to be enough time to talk about the data table and the graph before we flip over though look at what the data table has to have so it has to have column headings that are clearly labeled with the correct units and it has to have data included for all the trials with averages show now let’s look so glancing over at my datatable I need to have column headings so notice it says arm length in centimeters the thing in parentheses is the unit that I measured with so in this lab you probably measured with centimeters which is fine I probably would have preferred if you had used meters because you know these things are bigger than a meter stick and that’s also just one of the standard units we use in physics but if you use centimeters that’s okay now if you used inches inches are bad and you know why inches are bad they’re bad because when you look at a ruler and you look at the little lines between like one inch and two inches they’re not decimals it’s not like 1.2 and 1.4 and 1.6 like it is with centimeters they’re fractions so it’s 1 and a 16 1 and n 81 in 316 I mean no one wants to be writing down one in 316 and you definitely don’t want to have to do math with one in three sixteenths if you’re having like square that or multiply that it’s a lot harder to do those things with a fraction so just start with decimals start with centimeters in the first place okay we never never never never never use inches in this class the only time you really want to use inches later on in life is if you’re a contractor because still in this country we do measure things like cabinets and the heights of buildings in feet and inches but pretty much everything else we do in centimeters and meters and kilometers and stuff like that because it’s just they’re just better all right so as long as you’ve got that you’re probably going to get a 10 on your data table it does say that you have to include multiple trials on your data table so it could say something like this change this that’s weird sorry about that we could change this to say 150 and then maybe the next time we measured we got 149 and then maybe the next time we measured we got 150 again so that would show multiple trials but we didn’t necessarily do multiple trials in this experiment so we’ll leave that until later well I’ll remind you of that for your next lab okay coo and then the last thing that we want to look at is our graph the graph has to be labeled in exactly the same way you have to have what you measured with the unit over here so it says height in centimeters it says arm span in centimeters it doesn’t matter which access you put them on doesn’t matter but height on the top and harms fan on the bottom or vice versa either one is okay another thing to notice about your graph is something that you probably are not used to doing but you’re going to get really used to doing by the end of physics and that is drawing something called a line of best fit notice a line of best fit which I’ve drawn here does not touch all the points it’s just a straight line imagine like laying a ruler down and drawing a straight line that’s as close to all the points as possible so like when you’re drawing a line of best fit you wouldn’t want to draw it like this you know that’s pretty lousy that’s really far away from all the points but this is about as close as I could get to all of the points without overlapping any other so that’s line best fit make sure you