# Tagged Questions

The description of the movement of bodies by their position, velocity, acceleration (and possibly higher time derivatives, such as, jerk) without concern for the underlying dynamics/forces/causes.

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### Why does a curved spacetime result in a movement?

If gravity is not a force but a curvature of spacetime, where does the motion towards the center of gravity come from? To put it differently, why would two objects in a space fall towards each other ...
1answer
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### If an object launches off of a table at a given velocity, calculate angle below the horizontal when it hits the ground?

So this is a basic kinematics question that I'm having trouble understanding. Here is the question verbatim: A hockey puck slides off the edge of a table with an initial velocity of 28.0 m/s and ...
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### Calculating stopping distance of a car on a slope

I'm having trouble setting up a homework problem properly. We are given the following: A given car can brake to a stop from a speed of 60.0 mi/h in a distance of 123 ft on a level roadway. What ...
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### A couple of questions regarding work to velocity exchange [closed]

I was tasked to express the velocity of the cube of mass $m$ at point B using the constants given in the picture below. Friction could be ignored, and the cube could be presumed to reach B with the ...
1answer
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### a question on work and kinetic energy [closed]

A bullet has a mass of 0.02kg and is moving with a speed of 10m/s. It can penetrate 10cm of a given target before coming to rest. If the same target is only 6cm thick, what will be the speed and ...
4answers
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### Intuitive explanation of the half in the $\frac{1}{2}at^2$ distance equation?

The full equation $$Xf = X_o + V_o t + \frac{at^2}{2}$$ is integrated from the velocity function (which was integrated from constant acceleration function), right? The problem is, I can't seem to ...
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### 3 Particle problem with a difference

Please read this completely, it is not the typical question you expect. 3 particles are at the corners of an equilateral triangle with side a. Assume that particle 1 is at (0,0), particle 2 is at (a,...
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### Finding the distance a spaceship would travel given a time of departure and velocity

Let's say a spaceship leaves Earth at a day t and with velocity v. Is there a way to know how many kilometers it will cover to arrive on Mars? This would be a trivial question were it not by the fact ...
1answer
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### How fast does a long object bent at the center need to be travelling in order to boomerang?

At an angle, of course. Standard pressure, average temperature, and calm wind. Bonus question: Can an object that is not bent boomerang at all? If yes, how different would the equations for this ...
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### a problem on circular motion [closed]

Question:A cyclist is riding with a speed of $7.5$ m/s. As he approaches a circular turn on the road of radius $80m$, he applies brakes and reduces his speed at the constant rate of $0.50$ m/s every ...
1answer
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### What's the formula for the speed of an accelerating car?

I am trying to find a formula that closely describes the speed of an accelerating car over time. I have found many graphs on the internet, but so far no formulae to generate them. For my purposes I ...
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### Position from velocity time graph [closed]

I have taken Calculus before but unfortunately no equation is given so I have to do it the old way. An object is at x = 0 at t = 0 and moves along the x axis according to the velocity-time graph ...
1answer
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### How Do Low Kinetic Energy and High Kinetic Energy Atoms Attraction differ?

Will atoms of 2 difrent energy levels electron and/or Kinetic attract more than 2 Atoms at he same energy level? Do 2 high energy level atoms attract more than 2 low energy atoms?
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### Equation of motion of a free particle

We know that the equation of motion of particle can be derived from the respective action. But in the book I am reading, the author is saying: ... timelike worldline of a massive particle is ...
1answer
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### overtaking acceleration [closed]

A driver travelling at 50km/hr,trying to overtake another car by pressing an accelerater.The acceleration behaviour of the car is (dv/dt)=1.22-0.015v,whereby v=speed in m/s,calculate a)maximum speed ...
3answers
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### What is the difference between accelerating and boosting?

My professor claimed in class that there was a difference between an acceleration and a boost. I don't really understand the distinction. If you want to go to a different inertial frame of reference, ...
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### Why is 7 TeV considered as a big amount of energy?

Considering that $7$ TeV is more or less the same kinetic energy as a mosquito flying, why is it considered to be a great amount of energy at the LHC? I mean, a giant particle accelerator that can ...
3answers
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### Kinetic energy of a rotating object

in an exercise, a linear molecule is being subject to a force applied on the edge in its axis. Then $K_1=\frac{1}{2}mv^2$, all is well. Then in the second point of the exercise, the force is applied ...
1answer
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### The Intersection of two periodic bullets at different speed?

I'm trying to find the mathematical equation or concept to calculate an intersection of two bullets at different speed. So basically it's like an intersection of two lines, but I'm trying to add time ...