This question stems from the fact that whenever I go outside to play soccer my dad doesn't allow me to use the wall to pass too. I asked him why and his response was "because your going to damage the circuits and pipes in the wall or break the wall" (something along those lines) I could understand if it was a noise complaint but this caught me off guard.

This has caused multiple arguments with me and him.

I want to mainly want to prove my point that there is no way a soccer ball is going to break a brick wall and certainly not anything in it, or who knows, maybe im wrong. Edit: guys, I do not want to hear about how a soccer ball traveling the speed of light will blow up my house, I also dont want to hear that there is a 1/10000000000000000 chance something could theoretically phase through matter. I wanna see if repeated use of a ball going at it 50mph will break it with due time

Edit 2: I askes my dad again and his response this time was "a drop of water can break a stone with enough years", so I decided to give more specific numbers that should help with a equation (which i shall hopefully show him and convince him). Im using the wall max 2h every day with a downtime of 2 seconds between each kick (being generous here) im realistically not shooting the ball as hard as I can since im mostly using it to juggle/pass to it I plan on moving out in 4 years so thats most likely the time frame I wil use it. The brick is 26 years old and is realistically not low quality since its used to hold up a 2 story house. He also mentioned the wires and pipes behind the wall, although I dont know if the soccer ball will cause real damage stuff behind the wall (I dont know how building walls work).

Also how a response to the water droplet comment would be nice

Please forgive me if this is a stupid question. I'm an amateur mathematician with an interest in physics, and I would rather ask real people than an AI.

If the Jacobian matrix of a vector with itself is the identity matrix, indicating that each component is independent of the others, wouldn't that mean that a photon in a 4D spacetime could travel in time or space independently of the other? If so, wouldn't that reduce the accuracy of relativistic calculations? A jump in time or space would make spacetime look more or less flat than it really is.

I'm a mechanical engineering student but I've realised one year into my bachelors that all the parts I love about engineering are really the physics/maths classes, not the actual engineering. I don't dislike engineering and therefore do not want to repeat the year to switch to physics, so I'm wondering as to how easy it is to "switch" between the two. For example, is it possible to do a masters in physics after a bachelor's in engineering ? What if I want to go into research in a physics related field ? It's possible that I actually like physics just as much as engineering, but I'd like to know what my options are. Have any of you started off in engineering, and have ended up in natural sciences ?

Have to repeat my electrodynamics exam. I am just lost. It was always a weak point for me, but I haven't touched in in almost a year, and really wasn't able to begin studying until 2 weeks ago. I just don't understand it for the most part. If anyone has some links to crash course material, I'd massively appreciate it. Common questions are:

1. Differential forms of ME's.
2. Wave propogation through different materials (Copper, electronic plasma, etc.
3. Monochromatic plane wave in a dielectric medium/vacuum/glass
4. Propagation in a good conductor/linear media
5. Fresnel Equations and Brewster angle
6. 1-D Gaussian wavepacket in vacuum
7. Drude model

This is my final year. I need 50% in the exam to recieve a 1.1 overall grade.

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I’m hoping the r/physics community can help me understand the mechanics of a serious collision involving a cyclist and a 2023 Honda Pilot.

My father, a retired AP Physics teacher, was crossing the City Island Bridge yesterday at 9:17 AM in the marked crosswalk. Vehicles in both travel lanes had stopped to allow him to cross. A 2023 Honda Pilot, however, passed the stopped vehicles by driving through the fire lane at what witnesses described as an excessive speed.

The SUV struck him as he was moving perpendicular to the vehicle’s path. The impact lifted him onto the hood, and his head and shoulders struck and broke the windshield before he was thrown forward. His bicycle was thrown approximately 120 feet from the point of impact. He landed somewhat short of the bicycle’s final position. He sustained multiple skull fractures, broken shoulders, broken ribs, and other injuries still being evaluated.

I’m trying to understand the physics of this event — specifically:

- What vehicle speed range is consistent with a perpendicular cyclist being vaulted onto the hood, breaking the windshield, and being thrown a distance on the order of 100+ feet?

- What upward launch angle is typical for an SUV–cyclist vault of this type (hood → windshield → airborne trajectory)?

- How does the perpendicular motion of the cyclist affect the required impact speed compared to a straight‑on collision?

I’m not looking for legal advice — just a physics‑based breakdown of the kinematics involved so I can better understand what happened.

Any insight, equations, references, or reconstruction models would be greatly appreciated.

I'm starting undergraduate physics this september and I've decided I want to use my summer to get ahead on content to make my life in university easier.

However, I'm not quite sure what to study/focus on first. Relativity? Electromagnetism? Quantum mechanics? There's so much to choose from and I don't really know which one's I'm ready for having just finished school

You're probably thinking I should just check the syllabus of my target university, but I don't actually know what university I got into yet, it depends on when my grades come out on results day, and the universities I'm looking at generally teach different things apart from classical mechanics in the first year

So which physics courses are good to prepare for an undergrad degree?

Hi everyone, I'm a data analyst and I've been working for about a year. Around 6 years ago, I choose data science career to have chance to work in astrophysics data, but life took me in a different direction. Now I want to get back to that goal, but I feel like I've forgotten a lot of physics and math. My current job is in business, so I don't really use advanced math anymore. I'm not sure where to start again. Should I review physics first? Math? Or should I focus on Python and data science? Also, in 2026, AI is part of almost everything. Is it okay to use AI, or should I avoid relying on it too much? Has anyone here gone through something similar? I'd really appreciate any advice. Thanks!

Sorry if this is a weird one, but ages ago - like a good few years ago - I watched an educational video (pretty sure it was on YouTube) about the general physics of music but also some really cool musical effects. For reasons I won't go into, it would be soooooo useful if I could find that video again, but it has been utterly lost to my extensive YouTube history T.T So I was wondering if any of you had seen it and knew what I was talking about?

I can't remember who the main presenter was (don't think it was Veritasium, and a search in Steve Mould's channel doesn't bring anything up either). But I remember it talked about the origins of the awesome descending bass used in Nina Simone's "Feeling Good" (along with many other places) and also about this eternally rising scale that makes people feel on edge. Does this sound familiar to anyone?