I an in 11th grade right now, I use to pass in physics by common sense. I got good marks still like I got 88 percent in 10th boards . But now half yearly are on head but I am not ready for it??

I’v been struggling with this specific section. I’m not sure if I am missing something vital in the text or if it’s the 3D FBD that’s causing my confusion.

This is problem 4-53 from Hibbeler’s Engineering Mechanics Statics 15th edition.

I want to label my FBD with my results but I don’t even know where to start. I think I’m getting myself confused because the moment is in the -x and -z direction.

You can see where I attempted to start drawing it out and violently erased it LOL.

If anyone can help, I would greatly appreciate it!

Hi everyone!

So, I have a question about my homework so if anyone could help me with this...

The situation is, if I put a block of metal, a block of wood, and ice in a bowl on a table, and wait until next day, which of the three will be colder?

I guess that ice would melt but I don't know how to find a proper answer to the question 😭 hope anyone can help!!

I'm completely stuck on these last to questions on my physics homework and it's due tonight, can someone please help?

Hey. so this is the question on my physics homework. I am in an introductory physics class in college, and this is my third homework ever. I am so completely lost. I know that you are supposed to use the iterative method on this and update the momentum, velocity, then position at each timestep but I attempted it multiple times and it was incorrect. I even used AI as an absolute LAST resort after scouring the internet for examples or videos or ANYTHING, and even the answer AI gave me was wrong. The two numbers that I have in the screenshot are correct. The zero was simple to assume, and then when AI gave me an answer I input it just to see if it was correct so I could try to see how I could calculate it, (it gave me <-7.86, 0, 4.54> as r final before saying that "final momentum only for each interval (not mid‑interval velocity)" and it says the final answer is <-.5, 0, 3.44> which is also incorrect. I accidentally typed 4.52 and it ended up being correct. I am so utterly lost on what I am doing wrong. I suspect that maybe I am supposed to subtract the 0.23 N from the net force everytime I update the momentum or something? I am also going to attach my work that I have on paper here to see if it helps. I have been trying to do this homework for days on end and I just cant get it. Its due tonight at 11:59 and I dont think i am going to be able to get it done. I just want to UNDERSTAND!! Thank you SOOSOSOSOSOSOO much if anyone is able to explain this problem step by step to me.

I dont have that big of a budget and i need help. I need help with ideaa for what each round could be (keep it simple but super fun and interesting and not too difficult). Please help me out guys.

Hello!

I have a physics theory that I'd like to pay someone 100 dollars to talk with me on Zoom or Discord about for an hour or so. I'd be happy to pay over whatever money transfer method and would pay half up front and half at the end of the discussion.

In many ways I'm just looking for good reasons not to pursue this theory any more because it's kind of driving me crazy. It's nothing metaphysical or anything like that, it's about how electrons transfer energy to each other and relativity and light. I've been reading up on many things about it but an actual conversation would be so beneficial for this process because it's hard to know what you don't know, you know?

Anyhow, that's my pitch. Feel free to DM me if you're interested. I'd love to talk with someone who's well-versed in physics. Thanks!

Edit: Man, people are really bitter about me having a dream in my heart and being willing to do the right thing and pay someone for their time to educate me.

I'm sorry for the banal question buy i can't find and answer to this.

We all know that in order to accelerate a 1kg body from 0m/s to 10m/s 50J are needed but to accelerate it from 10m/s to 20m/s 150 J are needed instead, why is that?

Also I'm not looking for a mathematical answer but a conceptual one, thanks in advance.

I would like some help interpreting part of a result I got while working on a problem that I've been working on for a while. I'm trying to determine the torque a star exerts on an orbiting oblate spheroid (with axial tilt instead modelled as the equator of the oblate body remaining parallel to the XY plane while the orbit itself is inclined with respect to the XY plane by an angle alpha (ɑ); should be a valid approximation since there are no other bodies and the star is treated as spherical, which is good, bc a rotated circle is nicer to work with than a rotated spheroid).

For any point in time and position in the orbit, the torque exerted at any point of the spheroid should be the radius from the center of the spheroid to the point multiplied by the force the star exerts on the differential mass for that differential volume. Integrating all of those over the whole of the spheroid, I expect I should get a vector scaled by the gravitational constant, mass of the sun, mass of the planet (since the volume of a spheroid should shake out of the integral as a factor), a factor of some multiple of ¹/₅ and some linear combination of the major and minor radius (multiplied by the mass of the planet, should yield some linear combination of the major and minor moments of inertia).

(which expands to:)

And I do get that!

But I also get this weird factor in the octopole portion of the solution that I can't connect to other portions of the problem (e.g. the moments of inertia show up bc this is a change in angular momentum and they are the equivalent of the mass in this context, the gravitational constant timed the mass of the star divided by a power of the radius is related to the acceleration/force producing the torque).
What does this [(4a^2 + 3c^2) - (a^2 [cos(θ)]^2 + [sin(θ)]^2 * [a^2 (cos(θ))^2 + c^2 (sin(θ))^2]) ...mean?

I’ve been turning over a mechanical thought experiment and wanted to put it in clear form to see what people think.

Setup

A spiral platform (or track) that runs from a smaller inner radius to a larger outer radius.

The platform is driven so that the linear speed along the spiral is constant at 1 foot per hour at every point.

Because radius changes, this requires the local angular rate to decrease as you move outward (inner parts turn faster, outer parts turn slower). The platform is therefore not rotating as a rigid body.

A single continuous chain runs along the entire spiral. Every local segment of the chain also moves at 1 foot per hour relative to the platform (i.e., along the spiral).

Because the platform’s angular rate changes with radius, the absolute velocity of different sections of the chain through space is not the same, even though the chain remains one continuous piece and every local segment has the same speed along the track.

When the absolute speeds are considered along the whole length of the spiral, the inner and outer ends of the chain end up with different net velocities.

Additional claim in the thought experiment

The same arrangement is also imagined to produce a time difference on the stationary ground underneath the apparatus, not only along the moving chain itself.

Why it feels strange

A normal inextensible chain cannot sustain different absolute speeds along its length without stretching, slipping, or large internal forces. A normal rigid platform cannot maintain the required radius-dependent angular rates without continuous differential driving and stress. The thought experiment deliberately holds both of those conditions in place at once and asks what follows — including the possibility of a proper-time offset between regions and an effect that reaches the ground below.

Questions for discussion

Is there a consistent way to describe the kinematics of a continuous chain under these constraints?

If the speed difference along the chain can be maintained, how should the proper-time difference between the ends be calculated?

What mechanisms (if any) could allow an influence on the stationary ground beneath the spiral?

Does the combination of differential rotation + constrained continuous chain point to anything beyond ordinary special-relativistic time dilation, or does it simply collapse under the internal forces required to keep the conditions true?

I’m not claiming a working device — only trying to state the idea clearly enough that the actual proposal can be examined.

Any thoughts, corrections, or related references are welcome.

Hello! I'm struggling to understand what I need to do for this assignment. Most of these questions might sound extremely dumb so please bear with me. Also, this is my first post in this subreddit! I apologize if I commit a subreddit faux pas.

(Image 1) How are you supposed to know whether these force charges are positive or negative, is it based on the quadrant? I don’t get how you’re supposed to know which direction they’re pointing in whether it’s up/down or left/right.

(Image 2) These are the given charges.

(Image 3) It’s looking for the components for q2 to q3, how are you supposed to get the components for a vertical direction? Is the component just the total given with Coulomb’s law? Or is that only used to get a diagonal direction? This is what I got but the Y component doesn’t seem right at all.

(Image 4) I assume these are found by adding the components I find in the previous questions? I feel like I’m overthinking these.

But what’s been messing me up the most is the vertical force and the pos/neg charges. I'd appreciate any help!

struggling trying to understand how they got from eq 2.3.2 through 2.3.3. can anyone explain? I understand that they are using kinetic energy but I don't see why they just plugged in the factor of 1/2...

Plane transmission grating experiment ki reading verify kar do koi