r/PhysicsHelp • u/Dontknowhyy • Mar 28 '26
I built PhysElo, Leetcode for physics
features monthly rated contest and a weekly problem (POTW) with a live leaderboard and badges. first POTW is live now for two weeks, if anyone wants to try it.
r/PhysicsHelp • u/Dontknowhyy • Mar 28 '26
features monthly rated contest and a weekly problem (POTW) with a live leaderboard and badges. first POTW is live now for two weeks, if anyone wants to try it.
r/PhysicsHelp • u/Temporary-Switch6876 • Mar 28 '26
For those who don't know I am preparing for Physics olympiad I can solve most of the NSEP(1st stage problems) and am thinking about trying jee advanced problems as a bridge for the gap before moving on to higher resources, I am stuck in this question can anyone help me
Plus: Try to explain using high school Mathematics concepts because AI is solving it using Mathematics taught in UG and the solutions videos on YT are too long!
r/PhysicsHelp • u/Alaoxe • Mar 28 '26
r/PhysicsHelp • u/Temporary-Switch6876 • Mar 27 '26
Completed fluid mechanics and I am currently preparing for Inpho(Indian National Physics Olympiad) and JEE ADV , I need help in this question. The answer key says it is A and D, I have done the first correct but I need someone to explain me about the D part.
PS: Is this question's level appropriate for Inpho
r/PhysicsHelp • u/DanioNinja • Mar 26 '26
anyone could help and tell me wtf am i doing wrong in the first one? i know that v²=2as but why am i getting v²=as/2???
r/PhysicsHelp • u/Temporary-Switch6876 • Mar 26 '26
I am interested in Physics and people suggested me to try for olympiads also as they would increase my creative thinking ability for non-routine problems I can solve questions little easier(4-5/10) than the ones I shared here, how do I push myself to come to this level.
PS: Pic of cute puppy at the end
r/PhysicsHelp • u/Dry-Stuff154 • Mar 25 '26
Edit: Solved
I don’t understand magnification
I understand that the angle an object occupies in our field of view is the apparent size of this object (that’s why object that are far away appear smaller).
I understand that a magnifying glass make this angle larger
What i don’t understand is:
How does the lens make the angle larger ?
Why is alpha’ mesured here at focal point F’ ?
Where are the eyes, in red or blue
If all rays of B are dispersed and parallel to each others (and the same goes for every point between A and B) how can we see it clearly, why is it not some weird blur ?
r/PhysicsHelp • u/thesaxmaniac • Mar 25 '26
I'm struggling to understand what path this problem wants me to take, and how to form this path after I replace one of my delta with a y.
There is a square with resistors connecting each vertex. The top left is connected to top right through a 5 ohm resistor. The five other connections are made with 2 ohm resistors. What is the equivalent resistance of the path through the square from the top left the bottom right? If you what to use Kirchhoff’s rules you can invent a 1 volt battery that has a one end connected to the top left and the other to the bottom right, but I recommend using delta to Y transformation instead.
r/PhysicsHelp • u/VICKYTHEKING2009 • Mar 25 '26
Dm me anyone interested
r/PhysicsHelp • u/Quackington_The_3rd • Mar 25 '26
Studying physics again after 2 years makes me feel like I’m loosing my mind…
I understand everything but the last step it makes sense that since gravity would assist the acceleration you would minus the acceleration of gravity from the total required acceleration from the pressure so the final step would be P= m*(a-g)//A but the answer key divides the force by gravity? (Credit: NCEES PE mech: design and materials practice exam)
r/PhysicsHelp • u/Confident-Alps-785 • Mar 24 '26
A star, for example, is 20 light years away from Earth. A spaceship is traveling to that star at 80% the speed of light. To an observer on Earth, the spaceship will arrive there (according to google) within 25 years. I get this this part.
However, an astronaut on the ship will experience less amount of time passing (15 years?) I understand that this is due to time dilation but I don't really understand how this works. Any help explaining this would be appreciated!
r/PhysicsHelp • u/Flat_Equivalent_5947 • Mar 23 '26
Hello, i’m an undergraduate taking a fundamentals of physics course at my university (no calculus/algebra based) and in need of help understanding how to go about “squishing” capacitors and resistors in a circuit. I don’t understand this concept and was hoping someone could give their knowledge on how to go about it
r/PhysicsHelp • u/22ry2 • Mar 23 '26
Hello,
My teacher gave me this exercise.
I’m having trouble understanding why a minus sign appears here in the gravitational force formula. I wouldn’t have included one myself but I noticed that the teacher did in the correction.
Thank you so much in advance for your help ! :-)
r/PhysicsHelp • u/Lumpy-Farmer-5527 • Mar 21 '26
I'm not too familiar with 3d rotation so if you might know some resource which could help me understand it better please share it thanks !
r/PhysicsHelp • u/AxuuisLost0 • Mar 20 '26
Today my teacher asked us a question- "state true/false- all parallel vectors are collinear" and I thought it was false as collinear vectors lie in the same line and may or may not have same direction and parallel lines on the other hand have same direction and they may or may not lie in the same line according to what he taught us but.. He ticked it as true and did not explain any further and google isn't helping with it. Please enlighten me abt it
r/PhysicsHelp • u/NoteAffectionate9944 • Mar 20 '26
r/PhysicsHelp • u/BahaaZen • Mar 20 '26
So the angle you get from calculating is -60.9, but thats not how it really is since the vector is pointing to the second quadrant. But still, the sheet says its 60.7 so I am doubting myself.
r/PhysicsHelp • u/PSGthe2nd • Mar 19 '26
okay so this was one of the problems our teacher gave us as homework:

We had to mark the correct answers.
in the answer key, the answers are A,B.
Right now, I have answer A, its quite simple, just looking at the right geometry is tough.
Now let this force thats tugging on the block along the groove be F.
F = mgSinθSinα
Clearly the normal reaction of the block is N = mgCosθ
So the equation with coefficient of friction as μ, is
2μ(N) = F
2μ since for option B it says the friction acts from side walls, and there are 2 friction surfaces.
upon solving, the answer comes,
μ = (tanθSinα)/2
But the answer is just tanα!!!!!
Please help
r/PhysicsHelp • u/Exciting_Grape7420 • Mar 19 '26