Acceleration Definition and 1000 Threads

Hello everyone, I have a hard time to conceptualize the case of a moving black hole. We know from SR that time slows down for moving objects; but time dilation at the event horizon is already equal (tends) to zero. It seems that it can create some sort of conflict for the black hole movement...

A particle traveled in a straight line in such a way that its distance (S) from a given point on that line after time (t) was S= 20t^3 -t^4 The rate of change of acceleration at time t=2 is what value?ok, I am kind of stuck on this very simple problem. It should be as simple as taking the...

for (a) ##T=\frac {2\pi}{\omega}## $$\omega=\frac {2\pi}{T}$$ $$\frac{d \omega}{dt}=\frac {-2\pi}{T^2} \frac {dT}{dt} $$ $$\alpha=\frac {-2\pi}{(2.94*10^-15)^2} = 7.27*10^29 rad/s^2$$ for (b) I'm understand that it's infinity, because the period is increasing indefinitely, so it's slowing...

Mentor note: Moved from a technical forum section, so missing the HW template. Summary:: Integrate acceleration when a = f(v) when separation of variables is not trivial, ie a = k +v^2 When acceleration is a function of velocity, ie there is a friction force, you would separate the variables...

Distance: substitute t=5 into x=3e^(0.4t) 22.17m Velocity: v=dx/dt =1.2e^0.4t____(1) Sub t=5 back into (1) v= 8.867m/s Acceleration: a=dV/dt =0.48e^0.4t____(2) sub t=5 back into (2) a= 3.547 m2/s I am not sure if i am doing this right on dx/dt and dv/dt

Hello everyone, I would really appreciate some help with a challenge I am facing. The challenge is to accelerate a particle in a circular path, but the acceleration must be non-uniform. In other words, the velocity does not increase linearly. The problem I am facing is shown below: The...

assuming initial velocity is 0 and we have the value for acceleration I'm unsure how to still use any of those equations because you must have a time value at least or a final velocity

I haven't gotten anywhere. I don't find it possible to calculate this since Fg varies based on the Mass of the meteroide and because of that it will change acceleration. I thought about trying to remove m1 by making F=m*a the same as 𝜸(m1*m2)/r^2 since I think they are the same force. m*a=...

I have attempted but I don’t get anywhere.

Let imagine that car with constant 500HP accelerate but resistance forces don't exist (aero drag,internal friction in engine and transmision,tyer rolling resistance etc etc..) neglect fuel loss over time.. From 0-100km/h take in 4sec and burn 200mL petrol Will car accelerate from...

By analyzing 91,742 reported extra-galactic distances and their one sigma uncertainties for 14,560 galaxies, it was found that pairs of reported extra-galactic distances of the same galaxy differ from each other by 2.07 the reported uncertainties on average. In my opinion, this indicates that...

Hello everyone, I have to find the average acceleration in the intervals 0m - 30m, 30m - 60m, and 60m - 90m. Here is the table: Position (m) 0 10 20 30 40 50 60 70 80 90 100 Time (s) 0 1,89 2,88 3,78 4,64 5,47 6,29 7,10 7,92 8,75 9,58 My teacher has given us the answers, but we have to...

I calculate the gravity force F = mg = (-9806.6)*(5.26e-1) = -5158 (mm^2*kg)/s^2 I get the moment M = F*r = (-3.5e5)*(-6.81e1) = 3.5e5 (mm^2 * kg) / s^2 Where r is the y coordinate distance from origin to centroid J = (Ix'...

Hello, I understand that, for 1D kinematic problems where the acceleration function ##a_x## is initially given along with the initial conditions, we can use calculus (differentiation and integration) to get the position ##x(t)## and velocity ##v_x (t)## of the moving object. When the...

I have already concluded that the way to solve this problem is through (20 N - (3 kg * 9.8 m/s^2 * 0.16) - (2*(1 kg * 9.8 m/s^2 * 0.16))) / 3 kg I have several questions: Why do we multiply the second set of parentheses by 2? Why do we count the friction between the 1 kg box and the 2 kg box...

The correct option is given as (d) I think I am able to visualize the problem but not able to put it in the equations shared above. If the the two frames are moving away from the particle at ##4 m/s^2## in opposite directions we get the acceleration between the frames as ##8 m/s^2##...

For a particle moving in a straight line, if the velocity is zero for a time interval, the acceleration is zero at any instant within the time interval. I am told the above statement is true. If I look at the equations v = dx/dt a = dv/dt It looks like if the velocity is zero for a time...

Hello, I am attempting to correctly solve this problem, however I end up with an equation that is slightly different as the one provided in the textbook solution. For question (a) I get the same thing, just instead of cos, I have cos^2 and I can't figure out where I went wrong. My process was...

I would really appreciate some help with a challenge I have. It is illustrated in the figure below: Scenario: The moving object moves with linear velocity until it reaches P1. When it reaches P1, I need to create the motion of the blue dashed path. Whilst the object follows the blue dashed...

So the acceleration of point A was given by a force F exerted on cylinder that's along the direction of the stick, decomposed into the horizontal direction. so aA = F cos Θ The same force along the opposite direction is exerted on stick, and if we decompose that in vertical and horizontal...

Hi if I understand it correctly, this is the process to find freefall acceleration of a falling body. S=ut+1/2at^2 Initial time and displacement is zero so, S=1/2at^2 find acceleration a=2(S/t^2) graph for change in displacement over time squared a= 2(yf-yi/xf-xi) (f=final i= initial) I...

Shouldn't free fall acceleration be constant at -9.8m/s^2 until the object hits the ground and turns zero?

Im for some reason getting 1.58 s for time. I found 1.75 m as the head start distance and then I do d=d so: 2.45t^2 = 1.75t^2 +1.75 but the answer for "a" should be 6.45s...

$$\begin{aligned}v=u+at\\ \Rightarrow v=gt\\ \Rightarrow g=\dfrac{v}{t} \cdots (1)\end{aligned}$$ $$\begin{aligned}s=ut+\dfrac{1}{2}at^{2}\\ \Rightarrow s=\dfrac{1}{2}gt^{2}\\ \Rightarrow g=\dfrac{2s}{t^{2}}\cdots (2)\end{aligned}$$ $$\begin{aligned}s=vt-\dfrac{1}{2}at^{2}\\ \Rightarrow...

Hello, I am a 15 year old who has done research around the topic of why the universe is expanding at an accelerating rate, and how it will come to an end. After years of thought (since I was 11) I have come up with my hypothesis that time itself is accelerating and slowing down, and has been...

A particle is moving along the x-axis. It is uniformly accelerated in the sense that the acceleration measured in its instantaneous rest frame is always g, a constant. Find x and t as functions of the proper time τ assuming the particle passes through x0 at time t = 0 with zero velocity.I n...

Hello, I am trying to solve a problem involving a mass with known moment of inertia about an axis with a lever arm at angle theta and length r with a non-constant spring force acting at the tip of the lever arm and fixed distance away from the axis of rotation. I am wondering what the best...

I can't find any values of acceleration or rate of change of acceleration of the expansion of the universe when I looked it up and I need these values for a theory I'm working on that could supersede dark energy and show the universe is closed even if everything accelorating away from us and...

I've written in that only the first statement was False, however my classmates aren't getting the same answer? Please help clarify...

Was wondering if acceleration seems to be a more fundamental property/quantity in the universe as compared to velocity or distance because acceleration can be defined in more absolute terms in a frame depending on the forces acting inside that reference frame. Considering a very simple example...

According to this link here https://en.wikipedia.org/wiki/Relativistic_mechanics#Force , we can inverse the relation of force in terms of velocity and acceleration: $$ \mathbf{F} = \frac{m\gamma^3}{c^2}(\mathbf{v} \cdot \mathbf{a})\mathbf{v} + m\gamma\mathbf{a} $$ to get: $$ \mathbf{a} =...

As for example we see a large void, the Great Repeller, which in fact is an underdense region, and with respect to this region, matter seems to be repelled by this region. The explenation for that is that matter outside that regions pulls on the matter inside it. But if that is really the...

General relativity tells us that an object in free-fall is actually inertial, following a geodesic through curved spacetime, and not accelerating. Instead, it's objects like us, on the surface of a large body, that are accelerating upwards. Maxwell's equations also tell us that accelerated...

Image above is the question. Below image depicts solution. if F1 is removed then the acceleration of that mass must be sum of accelerations of remaining forces. Right?? But answer says that acceleration of that mass is equal to acceleration of F1. I don't understand it. Can someone explain it??

If I'm standing on Earth, is my time dilation actually greater than if I was in a rocket accelerating at 9.8m/s^2 in deep space due to me being in a gravitational field on top of the acceleration? Geodesics experience time dilation in gravitational fields, so it seems like there is an additive...

I would like to estimate the maximum acceleration (or deceleration) of an alpha particle that is backscattered by a heavy atom, like in Rutherford backscattering. I am interested in the order of magnitude, not in a precise value. I am assuming the collision is elastic. The kinetic energy of the...

For a case of electrostatic field (B is equal zero), how should the force acting on a moving charge be calculated if we want to take into account all the relativistic effects? Also would it be correct to calculate the acceleration of the charge as a=F/m, or should some other formula be used? For...

I am not able to understand the following paragraph from my Physics textbook;

[Moderator's note: Spin-off posts from previous thread have been included in this new thread. Also, the OP's re-post of the scenario for discussion has been moved to this top post for clarity.] Yes. Physically, scales measure a force (and indirectly the energy) in their frame. Consider the...

A particle moves so that its position vector is given by $\vec{r}=\cos{(\omega t)}\hat{i} + \sin{(\omega t)}\hat{j}$. Show that the velocity $\vec{v}$ of the particle is perpendicular to $\vec{r}$ and $\vec{r} \times \vec{v}$ is a constant vector. How to answer this question?

How to answer this question? Any math help, hint, or even correct answer will be accepted.

How to answer this question? I am working on this question. Any math help, hint or even correct answer will be accepted.

How come the solution requires you to do mv^2/4 when the formula is just v^2 /r?

I am not able to understand the following paragraph from my Physics textbook; "The velocity of an object, in general, changes during its course of motion. Should it be described as the rate of change in velocity with distance or with time? This was a problem even in Galileo's time. It was first...

I am just confused on how to find the normal force/ FN of the first object. My classmates are saying Fgy is the exact same as Fn but I don’t get why Fgy= Fg sin theta Fgy= (20)(9.81) (sin35) Fgy= 112.5 Fgy = FN

Distance= (Intial Velocity + Final Velocity / 2) Time 0.75 = (0+75 / 2) Time 0.75 = (37.5) Time 0.02 seconds = Time Acceleration = (Final Velocity + Intial Velocity) / Time Acceleration = (75 - 0) / 0.02 Acceleration = 3750 m/s2 Idk if this is correct can someone help pls.

Nevermind I found what I had to do, thank you though.

In the Lambda-CDM model, the density of galaxies goes decreasing and should even vanish in the far future. I would be grateful if someone could point me to a paper where this is calculated.

It seems to me as the space between galaxies expands it reduces the gravitational attraction between them. Assuming that this is happening between the majority of the galaxies in our Universe it would cause the acceleration of expansion by a factor of 1/r2.