Physics
For Physics Discussions
1,008 topics in this forum
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- 1 reply
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Hello. My problem is: I put the percentage uncertainty of a given value in the column. Of course, rounded it to 1 sf. The point is that for a given data set it is 0.7 %, for another 0.03 % (for instance). I don't know what I should do as I have to posses the same number of decimal places in one column. Do you have any idea? generally: is it also necessary to keep the same amount of decimal places in one column when talking about percentage uncertainties?
Last reply by cricketcrazynerd, -
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Hello. I've got question concerning appropriate notation of variables. Namely: I investiage photometric law of distance (inverse square law of light) and my RQ is: "How is the luminance of the light-sensitive area of the photoresistor dependent on the distance of photoresistor and source of light?”. The point is that to indicate how the luminance change, I measure resistance and iverse it, due to inverse proportionality of luminance and resistance. Hence, my unit for a luminance is not lux (as in the theory) but Ohm to the power of (-1). The question is: what is my dependent variable? From RQ, it is luminance. But I actually measure a resistance to get the relationship fr…
Last reply by yghydumdam, -
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I've just finished a set of 33 new videos that cover the entirety of the IB Physics SL and HL Topic 4: Waves Here is an outline of the videos (ones with stars are extras that aren't needed in the syllabus, but I thought were fun to add anyway) Topic 4: Waves Waves intro (transverse and longitudinal waves, explosions in space) Wave characteristics (wavefronts, rays, period, amplitude, wavelength) Wave equation (wave equation, thunder and lightning, buoy in water) **How a speaker works Electromagnetic spectrum (visible light, infrared, radio, ultraviolet, x rays, gamma rays - examples of each) **Breaking the sound barrier (supersonic, mach number, mach angle, planes, cars, …
Last reply by freezy19, -
- 5 replies
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I feel like crying right now. I'm doing so poorly (89% converted) and now the mock exam is gonna drive me down to like a 78. How does everyone study for physics? Like, I get the concepts from the reading, but when I try answering questions from the Tsokos book, I'm lost. Does everyone else feel that way? How do you best study for physics? I know of one guy who studied for his HL chem exam in one day because he spent all his time studying for HL math, so I hope I'm not totally screwed.
Last reply by MitchCampbell, -
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Hello, I am doing physics higher level and our teacher always gives us a lot of work to do and most of the time it's too much. I don't mean that the exercises are hard, the are but I would expect a teacher to give a few exercises as homework but our teacher gives us a few pages full with exercises. Is this normal, do you also get a lot of homework? And then our teacher says that the information physics is very hard and we don't have enough time to do every topic in full and therefore some topics we have to learn by ourselves? I personally just can't believe that the IBO made the syllabus so hard as she tells us. We aren't many in the classroom and she always tells us t…
Last reply by MitchCampbell, -
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Can someone please upload the Physics Course guide (LATEST)
Last reply by HiggsHunter, -
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Hello everyone, My physics teacher isn't exactly the most organized or helpful person in the world. While we have done several experiments, we never actually handed in an IA as I have done for other subjects. Turns out that we have to now rush all the IAs in the last 3 months before the final exam (yes, we're in the 2nd year). I (and my class) have tried asking him how and what to do, but to no avail. So my question is: how do physics internal assessments work? I know there are 3 parts being design, data collection and conclusion. What I don't understand is the number of IAs I have to write. Should there be 2 IAs for each of the 3 aforementioned categories? Or just 3 comp…
Last reply by Mc837, -
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My Physics teacher asked us to do a design experiment over the winter break and i have no clue whatsoever about what has to be done. I am supposed to figure out the effect on gelatin due to different temperatures. Am I supposed to make the jelly and do the experiment??? Please help... If you can post links to follow on to it will be really helpful!!!
Last reply by dniviE, -
- 2 replies
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Hi, I wanted to include a physics example in my TOK essay, but since I don't take physics, I decided to ask for a little help. I want to write abt Abraham-Minkowski controversy. Obviously, I've done some research and I know what it is about. But I can't find any information what it applies to in general. I mean, if it was definitely resolved (some are arguing that it actually already is) what would the results mean? And what new does the "more correct" equation bring to physics? Maybe they both do but in different ways? I just need a simple explanation, if anybody has any idea about that I would really appreciate your help.
Last reply by maereth, -
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Hello everyone. I've got a question concerning Lab report. The situation is that I received 6 points from Design aspect. Thus, the theory, assumptions, etc. were correct. It was mainly about standing waves but I thik that's not the clue. The point is that I get 5 points from DCP aspect due to the fact that my line of best-fit was done wrongly (according to my teacher's view). Namely: I assumed (design) that if I put certain variables on axis (according to the theory of standing waves), trend line should be straight. That is why I drew it straight but unfortunately, it didn't pass through any error bar. The real pattern of points was rather kind of polynomial. And here goe…
Last reply by Procrastination, -
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So, this is possibly a random topic that I've just created because I'm bored. Actually, no, I'm procrastinating and avoiding writing a thermal physics CE and studying for a topic quiz both for tomorrow. Everyone seems to think that physics students are crazy for taking such a hard and meaningless subject. Why bother? Why not do bio, which is just memorising stuff? To be honest, this is the question I ask myself, and I never seem to find an answer. Why, oh why? But deep down, I know I love physics It's the mystery, it's the power that physics has over fundamental concepts like space and time, and that other sciences can never really reveal. It's almost like magic. S…
Last reply by Marazm, -
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I have a physics lab due next week, does anyone no how to calculate the error percentage of the following readings? 0.09616677875 N 0.2645755989 N 1.978381515 N 0.07387299429 N 0.1962737545 N
Last reply by ChocolateDrop, -
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Hi, I'm doing a design on cooling abilities of ice cubes and I would appreciate it, if you could help me with this a little. In my experiment, I was immersing 1, 2, 3, 4 and 5 ice cubes (those are my independent variable) in a hot (80C) tea. Then, after one minute I checked what the temperature change was. I don't think my results are very consintent, and therefore, I would like to ask what kind of relationship between the rate of cooling and number of ice cubes would you expect from such an experiment and what factors do affect this rate.
Last reply by Dr. Jenkins, -
- 2 replies
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The index of refraction for blue light of wavelength 4.5 X 10^(-7) m for a particular kind of glass is 1.328 and for red light of wavelength 6.5 X 10^(-7) m it is 1.321. An equilateral triangular prism is made out of this glass and white light is incident on it parallel to one of its bases. Find the angles the blue and red rays make with the normal as they emerge from the prism. What is the deviation of each ray? Solution: The fact that the solution is an angle would hint that Snell's Law must be used. However, Snell's law only applies to refraction from a rarer to a denser medium, and in this case the light rays, emerging from the prism, are traveling from a denser to a …
Last reply by macrofire, -
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- 707 views
Hello. I've got a question which is connected with my physics design - hitting the glass with a hammer and checking the frequency of the sound. The independent variable is amount of water inside the glass. How would you describe the theory of physics as far as this investigation is concerned? Of course, I don't want the whole specific answer, rather some tips because I don't know actually how to start with it. Of course mentioning the theory of sound frequency, etc. that is obvious. But I don't know hot to put the reason why the sound is emitted by hitting the glass. I will appreciate any answers. And I've got one more trouble. I don't know actually whether the frequency …
Last reply by macrofire, -
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Hi guys! I'm kind of new here. I have a trouble finding the format of the Design Lap Report. I have some ideas about what I'm going to do now but I do not how to write the report! Are there any example so that I could take a look? Thank you so much !
Last reply by khimberleigh, -
- 4 replies
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I move around a lot, so taking the IB was rather ideal for me since I wouldn't have needed to change systems or subjects (provided that the school offered the normally available IB courses). I just moved schools approx. two months ago, and I haven't had any trouble with my subjects apart from Physics. Initially, I took Physics at SL (as I didn't enjoy Biology nor had any previous background knowledge about Chemistry), but the new school here doesn't offer Physics and Chemistry at SL, only at HL (which I find rather weird). It's one of those schools that do their SL courses in one year as opposed to two; I suppose SL Physics and Chemistry were not that popular compared to …
Last reply by Sandwich, -
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Hi guys. I just want to ask if somebody will help me about this. I have a problem in thinking of a good design lab in Physics. And I know it's easy to just think of formulas or something but you need to include BALLOON in your experiment. So what is the best Design Lab. Please help me. Please help me.
Last reply by Zostale, -
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I need a good idea for my design lab in which we have to use gelatin... helppp pleasee
Last reply by Procrastination, -
- 1 reply
- 736 views
Hi I have to create a design from my HL subject, i mean Physics, directly thermal physics and i have no idea what can i do with this topic. If you have some concept, can u share with me or just steer. Thanks in advance.
Last reply by CkyBlue, -
I don't know what to do anymore. Help :(
by Guest Loco Mo Mo- 8 replies
- 2k views
Hi, Erm, I don't really know why I'm posting this. I guess it's a cry for help. My physics exams are in a little over a month and I honestly feel like I'm screwed. The Easter holiday started about 4 days ago and I've done absolutely no revision for physics. I try and sit down to make condensed notes from the textbook but after about 5 minutes, I get bored and start to procrastinate. I've tried just doing exam papers but everytime I do, I find myself having to look at the textbook almost every other question. The thing is though, I want to do well. So bad. I just cant bring myself to do it. It's just well, I don't know what to do anymore. I feel like I'm completely…
Last reply by ChocolateDrop, -
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I can't think of a suitable (yet a bit original) experiment with electromagnetism for a coursework. Are there any suggestions twas what I might do? Thank you in advance
Last reply by TheBandman, -
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A cell is connected in series with a 2.0 Ω resistor and a switch. The voltmeter is connected across the cell and reads 12 V when the switch is open and 8.0 V when the switch is closed. The answer is supposed to be 1 Ω, but I can't seem to get there! I've tried using the formula V=emf-Ir but i seem to be doing something wrong. Any help with this question would be appreciated!
Last reply by HiggsHunter, -
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Hello, I've done an experiment where I investigated how the length of an conducting wire (in this case an iron wire) affects its resistivity. I know, according to theory, that the length is proportional to the resistance but how could I compare it with my own results? The R-square value of my graph is 0.9996, almost 1, which suggests that it seems to be linear. But again, to the question: How could I compare my results with theory? In chemistry it's just looking up a certain value in the Chemistry Data Book, but in physics you often investigate relationships. And how do you compare that? Note: I can't compare the resistivity constant since I did not measure the temperatur…
Last reply by IB-Adam, -
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I just finished a lab that investigates the relationship between the mass and velocity of a water rocket. After plotting mass against velocity, I got an upside-down quadratic equation like graph. Even if I do make it a linear graph by altering variables, the gradient doesnt mean anything. The "product" of the two actually gives Momentum. What should i do? My teacher says I must plot the straight-line graph even if the gradient doesn't mean anything. Moreover, do i have to explain why 'X' mass gave the highest velocity? And do I have to explain in detail why the graph is how it looks like it is? I realised too late that this lab takes into account changing mass as time pas…
Last reply by flinquinnster, -
- 1 reply
- 960 views
Does anybody know when there is a uniform field acting normally to the plane of paper, why do we consider the field as a magnetic field not an electric??? and how could we reference to the circular motion in order to justify the answer?? also can anybody explain this formula or at least its symbols r= (mv)/(Bq) Thanks
Last reply by Beni, -
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Hey, so as you might be aware as of now, I need help with my lab. The experiment itself was observing the time it took for a cart to go through 2 points on an angled ramp (The degree of the angle varied as it was a independent variable). I have the cart mass and a vague idea of how I should proceed, I am not sure of what to analyze, whether it be the Acceleration, velocity, instantaneous velocity and its relation to the angle of the ramp. The goal of my thread is to point me in the right direction on how to process the data. Thank you.
Last reply by Terminally in Hospice, -
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Does anyone know how people are marked overall for Physics HL? What I'm referring to is how much of our mark is based off of labs, group 4, and exams. Also, does anyone know the overall grade ranges for each mark? This would help a lot, thanks
Last reply by aangel, -
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Hello IBS, i'm doing a design experiment on SMH and i've run out of ideas. I tried to study the energy changes when a pendulum bob colides with a cart in the floor, but that turned out to be too complex. Now, i don't know where to even start as my classmates are already analyzing the effect of the length of the pendulum string, the mass of the pendulum bob or the amplitude of oscilation. Someone else is doing something related to springs, but it has a lot of uncertainities. What should I try to study? I was thinking of measuring speed, but not sure how to!
Last reply by Sword (Hubert Pomorski), -
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Please help me out with this one. 1) I measured the time taken for 10 oscillations and got the following results Try1 6.84+/-0.02s Try2 6.65+/-0.02s Try3 6.66+/-0.02s Try4 6.56+/-0.02s The average of these results is 6.68 seconds. But how do i calculate the error of the avarage? Is it 0.08s or 0.02s? 2) I used a stopwatch for measuring the time taken and its accuracy is 10th of a second. So i basically got times like 20.54 seconds. Now, because of the large error that's possible , can I take the error as 0.1 seconds even though my values are 2 decimals? Thank you.
Last reply by Sword (Hubert Pomorski), -
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I have been wondering about a couple of topics on which i can design lab but the thing is that some of them are just too "easy" in a way that they just won't be acceptable by my teacher and others are too hard for me to do. I'm looking for something which can produce good number of results. I'm being graded on design so i don't really care about CE and DCP but i want to formulate a good question. Topic which i was thinking about were: - investigating properties of bouncing ball - investigating properties of a spring - investigating the pressure of gas About the pressure of gas, what can i focus on? I'm too confused to come up with the question so please help me out here …
Last reply by yami.mthr, -
- 5 replies
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My physics teacher gave us the aim of the experiment and it was " To show that the time period of a simple pendulum is irrespective of the mass " . This is a DCP and CE lab. Is this topic good? Can we ask her to change it? Or will we be analysed solely based on our DCP and CE and not the aim?
Last reply by yami.mthr, -
- 6 replies
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Could you please help me with my first physics lab design? I need to design 2 experiments: one about coffee cooling and the other one about popcorn. I know these are really weird topics but our teacher gave us them to practice. I formulated some research questions to these topics, but i don't know if they are correct. 1. How does the temperature affects on the speed of coffee cooling? 2. How does the temperature of oil affects on time of making popcorn? Assess my questions and define variables (because I have a problem with it).
Last reply by caroline.st18, -
- 13 replies
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I find the current IB HL Physics book some what dry. It lacks information about many of the examples it does, and why things the way they are. Does anyone know of a better book that could teach me deeper into each of the subjects?
Last reply by The Economist, -
- 1 reply
- 536 views
any good reference books for physic hl/ sl ?
Last reply by CkyBlue, -
- 5 replies
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Attempting the practice questions in the Tsokos book, I can hardly do any of them!! Why are they so hard?? :'( Yet, in the exam I can at least answer most of the questions. Does anyone else find the Tsokos questions near impossible?
Last reply by pravzcool, -
- 3 replies
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I have an IB Physics internal exam tomorrow on all the core aspects of the syllabus, which if you're not aware of are: Physics and physical measurement Mechanics Thermal physics Oscillations and waves Electric currents Fields and forces Atomic and nuclear physics Energy, power and climate change And during revision, I've noticed that there are a lot of important formulas that aren't on the formula sheet, and can't even be easily derived (at least in my opinion) such as for instance: ω = sqrt(k/m) or F = 1/T So what are some other of these formulas that will be important in the exam, and aren't already in the formula booklet, that I should keep in mind? Thanks
Last reply by CkyBlue, -
- 1 reply
- 714 views
My teacher has explained it to me before but I didnt really get it. Can someone tell me how the different criterias and the points you get for them work. And also, what is the overall total score one can get?
Last reply by CkyBlue, -
- 1 reply
- 607 views
We did like 10 unit tests in physics HL, the first IB yr. I got 8 strong 6's and 2 strong 7's. But I was predicted a 6 in Physics HL last yr. But Ive been reading up and feel like I am understanding more concepts. So I was just wondering if I start pulling many 7's when IB2 beggins if whether my teacher would actually give me a 7 or give me 6 based on the fact that I mostly got 6's in IB1?
Last reply by Sammie Backman, -
- 2 replies
- 701 views
Anyone reading this book? Currently 30 pages in and I'm finding it pretty great. Wish I'd read it when I was still in the IB. I did Physics SL and literally did not understand any of the stuff at all. Double-slit experiment, Bohr's model of the atom, Planck's constant - all of those things are explained here so clearly that even the dummest person gets them. Don't you think textbooks in general should approach this way of writing? I mean non-fiction books do it so much better: they engage, they're funny, they're simple. That's what you need, especially with something as complicated as physics.
Last reply by flinquinnster, -
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Ok so according to the sample ia in the textbook i have, there should be two tables, raw data table and processed data table. I have calculated the uncertainties in time in the raw data table but now in the processed data table i'll calculate the period for each length of the string. 1. How can i calculate the uncertainty again for the period so that i can plot it on the graph 2. Should i have two graphs, one based upon raw data and the other one based upon processed data or just one based upon processed data?
Last reply by Nabz, -
- 2 replies
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Hi guys, I've recently done my final exam on physics SL as an anticipated subject, and I have to say it went quite well (pretty sure I'll get a 7). I'm good at physics and the reason I didn't take HL is because our school didn't offer it. Now I'm going to apply to American universities, and they require the SAT II subject tests, and I'm planning to do physics as one of them. So I became concerned about what is the level of SAT physics compared to SL physics (because I'll need a VERY good score from it). If it is more difficult or has more content, then could you please tell me what exactly should I learn? I'm good at physics and there won't be much problem in studying som…
Last reply by norsul, -
- 9 replies
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I'm kinda new to the whole Physics Lab Reports section. I was wondering if this would be a good question to address for my first lab report. How can the the pressure of air and varying quantities of water affect the movement of a model water-powered car of a fixed mass along a horizontal track? Please help me out on this one.
Last reply by wireman, -
- 9 replies
- 5k views
My teacher just gave me the assignment yesterday and it's due tomorrow. What i have to do is design a lab on it and hand it in which will be graded as my ia... Problem is, we have been dong nuclear physics and all of a sudden we were given this...so i can't think of an aim and variables for this lab...can someone please help me out, i'm in deep trouble if i don't figure this out. EDIT: the picture we are given is something like this but instead of a rod, it's a ruler and on top, it's a 1m ruler as well but the oscillation shown is the way it should be..
Last reply by HiggsHunter, -
- 1 reply
- 1k views
if anyone know please share. i need the answers in paper 1 for physics sl may 2011. if anyone knows where to find them tell me.
Last reply by The Economist, -
- 1 reply
- 43.9k views
I found this a while ago, and have been using it every since. It has the answer for every problem in K.A. Tsokos's Physics for the IB Diploma (SL and HL). It not only includes answers, but also shows and explains the work done to get those answers. It is broken down by chapter and section, with each section as a downloadable PDF. http://www.katsokos....ySolutions.php Enjoy!
Last reply by HiggsHunter, -
- 4 replies
- 905 views
Or is it too early? I would really love to look over the HL TZ1 to see how I did. If they aren't available now, does anyone know when they will be available. I wasn't sure whether I should put this here, or somewhere in Exam Discussion, so I decided to put it here.
Last reply by The Economist, -
- 12 replies
- 1.4k views
i have a design lab to do and state what is the relation between length of spring and time period of a spring oscillation. however i tried to plot ln(time period) y and ln(length) x but i dont know what to do next. i dont know what the gradient that i will find will stand for.... Please help... maybe of you can tell what should the outcome of my calculations or something that would help me find an equation with time period and length of spring...
Last reply by Ace.face, -
- 4 replies
- 3.3k views
I'm Mitch, and I'm an IB Physics and Math teacher - most recently at Copenhagen International School. I've got a few resources available that you might find useful in preparing for your exams in May or November. First, if you take IB Physics HL, I have a full set of youtube videos that walk you through AHL Topic 13: Quantum and Nuclear physics. (It's also Physics SL Option B). Here's a link to the playlist: I want to let you know that I’ve just launched a new website with free video tutorials and study notes in mathematics and physics, as well as online revision courses in IB Math SL and Physics SL. The website is called www.studynova.com. The idea is to continuo…
Last reply by MitchCampbell, -
How did you guys find the physics HL exam this year? I am SO scared they will raise the curve since people are saying it was easier. I really think I failed paper 2 and 3. :/
Last reply by britney spears is awesome,
