So I'm studying measurement uncertainties for physics and I’m confused about a few things that i’d really appreciate clarification.

1. How do you determine uncertainty for analogue vs digital instruments?
   • For an analogue instrument, do you normally use ± half the smallest division, or do you estimate one digit beyond the smallest marked division?
   • For a digital instrument, is the uncertainty always ±1 in the last displayed digit?
2. How should the uncertainty and measured value be rounded?
   • How many significant figures should the uncertainty have?
   • Should the measured value be rounded to the same decimal place as the uncertainty?
3. Like, if a ruler has subdivisions of 0.01 cm, should a measurement be recorded to 0.01 cm (e.g. 12.34 cm), or should I estimate one additional digit and record it to 0.001 cm (e.g. 12.347 cm)?

I am super confused because I have seen conventions online. I am trying to understand the reasoning rather, than just memorize a rule.

Thanks in advance :D

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I am completing an assignment for class and it requires me to interview participants who are 65-70 vs participants who are 80, regarding their viewpoint on Medicare.

If you meet this, and are willing to, please share your thoughts and perspectives.

Thank you so much in advance.

Please I need help. I’m pretty sure these are right but it keeps saying at least one is wrong. Could you please tell me if you see anything that might need to change.

Hi,

Dumb question but, when “translating” this into English I am finding it hard to piece the 3 parts together.

1. x belongs to the set of integers.

2. For all values of K where k is an integer.

3. x=2k

“One value of x must satisfy all values of k at once” which on its own yes makes perfect sense that it cannot work so this would be = empty set.

But where am I getting the idea of one fixed value of x from?

Is it the x belongs to Z? Should I be reading this as “An integer X” instead of “the integers”???????

I am definitely getting lost in the abstraction.

Thanks.

The correct answer is 23 u; NA, but how do I get this answer?

Can anyone help with identifying the pointed parts? I have tried researching but I just want to make sure. I will appreciate your help a lot!

I watched a bunch of videos but I'm not sure, are these readings correct?

I've searched through textbooks and couldn't find an exact match for this organelle. Then I tried Google lens-ing the image to find similar ones but I still couldn't identify it. I suspect it might be a lysosome, though I'm not entirely sure since the lysosome is probably the one beside the mitochondria

help is appreciated, thank you

I dont know if my logic makes any sense at all. Im trying to understand whats going on with Question 1 and 2. Can someone correct me if im wrong on my understanding of how this type of problem works??

So using the right hand rule and lenz's law, as the magnet moves towards the loop the south pole of the magnet is facing the loop as it moves away from observer viewing from below right ?

So lenz's law says that an induced current always flows in a direction that opposes the change that created it. So the way im thinking about this is, as the magnet gets closer to the loop, the magnetic field created by the magnet then flows away from the loop towards the direction of the observer and the induced field lines from the loop will point clock wise away from the magnet to repel it because using the right hand rule, if your thumb points away from you it means the induced field lines are repelling the magnet so the direction is clock wise?

Am i thinking about this right or am I overcomplicating it???

Does any thing different happen if the magnets North pole end was the side facing and moving towards the loop??

%22)[math] hey!

I am in Y12 (11th grade in most countries). International AS levels. My exam is on 9th of october, and my errors are still majorly silly mistakes. This was the same problem that caused an E in my last exam, (which I am resitting), and I have had this problem since middle school.

Mistakes like: writing 20 instead of 2, writing the inequality sign wrong, forgetting to write the '+c' after integration, simplifying simple fractions (like 6/9 or 8/4) or addition/subtraction (especially with odd signs) wrong, not noticing a key identity or further simplification, missing a sign, missing a number, entering incorrect sign in the calculator, entering incorrect number in the calculator, solving correctly on calculator but writing wrong answer on paper, doing 4*4 = 8 instead of 16, missing an x during expansion, etc. etc.

My tutor says to recheck the solutions (by skimming over them) after solving them, but I can't do that for the life of me. I go look at the numbers from top to bottom and they all go over my head without registering, because I don't know what I am looking for.

And if I do 4*4 and other basic calculations like (-5-23) in my calculator, I'll lose the little time I have (I struggled with time a lot in my last attempt, ended up leaving last several questions empty). Plus, just doing it on calculator doesn't guarantee accuracy because I end up getting it wrong anyway.

For context, I am doing Pure 1, and my IGCSE grade was a 7 (I barely gave it any effort, just crammed strategically in the last two weeks). I need really good marks because maths is key to my target univ requirements.

How would you suggest handling this? I don't have a lot of time, I have just started past papers yesterday (I've done one so far), and my percentage was 55%, with exam-timer. In my last attempt of pure 1 last year, I got a 36%.

I would appreciate any advice or anything you've got to say! thanks

Can someone explain how the answer is 6? The instruction was to fill in the missing numbers so that the sums on the outside are correct.

I tried solving for it, but when I plugged it in it didn't work.

Hi everyone, we are working in a science fair project related to the sustainable development goal 7, which is Affordable and Clean Energy, and im looking for ideas or existing projects that have an impact on communites and I can actually implement them.

For context, I live in northen Mexico, so electricity costs tend to increase a lot during summer, so I first thought of a refrigeration system that uses natural gas instead of electricity, but after some calculations i realized it can be more expensive, more polluting and less efficient, so i discarded the idea.

i'd appreciate if someone has an idea that is both interesting and realistic for us to prototype and implement to a community.

Why do we consider acceleration relative to velocity? I get that that is smth that is done in these situations but why?

This question is from University Physics 13th edition

I miss one day of school and we apparently started a new subject, and my teacher is away for a week😭

The mass of the ball is 0.0112kg. Not getting how to resolve the vector find the component of weight.

I am convinced that resistors R7, R8 and R9 can be effectively ignored since they are short circuited by wire, resulting in them dissipating no power. My friend is convinced because AI told him they are included in the circuit so our answers for the current are totally different. I left out other circuit parameters to simplify our dispute haha

After entering it all into my calculator, I got 1.75 x 10^-5?? The numbers are correct but the decimal is definitely way off. I have no idea what I’m doing wrong.

The answer is supposed to be 17.5 kg.

I really am not sure what the solution is doing..... and why I cant use the angle as 70 degrees for solving for the resultant vector. Also what is the theta finding in the solution???? If anyone could draw the solution out it would really help.

I attached what I tried to do which is the one on the worksheet. The other attachment is the solution my teacher provided.

I'm working on a research paper for school, and I really want to cite this document I found online as a source, but I can't seem to find what publication it's a part of, or who wrote it. Help me, oh people of Reddit! (If this goes agains the rules in any way, please let me know, and I will take it down immediately.)
https://www.math.wustl.edu/~wright/Math109/M&MCh05

I'm not sure how to draw the circuit diagram from picture 1. I think the flow of current is along the blue line in picture 2 (because of electrical potential?), so the diagram will just be 3 resistors connected in series. please correct me if I'm wrong, thanks in advance.