Image 1 — Fact Check my Notes?
Image 2 — Fact Check my Notes?
▲ 7 r/PhysicsHelp+1 crossposts

Fact Check my Notes?

I’m auditing an online class so I don’t have a teacher to ask but I’m trying to make sure I have a good grasp on EM waves. Specifically what confused me at first was how radio/visible light pass through things like the air in our atmosphere and gamma rays don’t, but only radio and gamma rays can pass through opaque things like walls while light waves are blocked. This didn’t make sense bc I thought waves with similar qualities/wavelengths would be blocked by the same materials, but after some research I think I figured it out and tried to put it in my own words.

I just wanted to confirm that everything I wrote is at least accurate and I’m not getting anything fundamentally wrong before I move on. Thanks!

u/ecto-x — 13 days ago

Birthday Rocky!

Just wanted to share the bday present that my friend hand-made for me! He even added all the canon markings and details (which might be my fav part) I was so touched and I love it sm 🥲🥲🥲

u/ecto-x — 16 days ago

What's the deal with Sulfate's charge?

When I tried to look up "why sulftate (SO₄²⁻) has a charge of 2-" a lot of the answers said that its because its missing 2 more electrons to fill the outer shells. But I thought that "missing electrons" meant that it would have a positive charge? So i'm really confused. Why does it have a negative charge before it gained any electrons, and if it did gain electrons to make it negative, where did those electrons come from??? I am auditing an online course so I don't really have a teacher I can ask. Any help is appreciated!

reddit.com
u/ecto-x — 19 days ago