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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Acceleration in Space

Lets assume a body with a certain mass is in a region of space that has zero $g$ (or pretty close to zero $g$). Would acceleration in a straight line produce $g$-forces? Would that mass acquire ...
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1answer
41 views

Unit Vector Displacement [closed]

A particle starts from the origin at $t = 0$ with a velocity of $+4.0\mathbf{j} \text{ m/s}$ and moves in the $xy$ plane with a constant acceleration of $(6.0\mathbf{i} + 4.0\mathbf{j}) \text{ m/s}$....
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52 views

Is the Coriolis acceleration formula just an approximation?

The Coriolis acceleration given in textbooks is: $a_{cor} = -2\omega v$ When trying to understand the derivation, it seems as though this is just an approximation. And to illustrate this I give a ...
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1answer
49 views

Can I call the component of tangential acceleration towards center of circle as the centripetal acceleration?

In my textbook the definition for centripetal acceleration is given, "The acceleration produced by virtue of change in velocity direction is centripetal acceleration" This definition is irritating. ...
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1answer
79 views

At a fixed inital velocity, What throwing angle will give the projectile the most trajectory length? [closed]

This is a diagram of a projectile motion: Given a constant initial velocity, What angle gives the most trajectory length? By length I mean the length of the parabola from the point the ball is shot ...
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1answer
158 views

Is there mechanical strain on a wire along the direction of current flow?

The (attractive) magnetic force on two parallel wires can be seen by the two wires bending towards each other. This can be explained by the Lorentz force acting on the charges and the charges "pulling"...
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1answer
57 views

Inclined plane problem [closed]

This is the problem question from my textbook. My questions are concerning some formulas related to this problem. The force of friction is obviously down the plane. My initial question is: $F_{...
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2answers
559 views

Velocity time graph for a ball thrown vertically upwards and falling back down to be caught again by a person

I am currently studying AS level physics and having some difficulty understanding the shape of a velocity time graph that represents the motion of a ball being thrown upwards and falling back down to ...
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1answer
58 views

For an object in circular motion, does speed affect the amplitude of sound it creates? [closed]

First of all, I'm sorry if this is a stupid question and I've missed something obvious. I used to have an instrument that was a small drum tied to a piece of wood. When you hold the wood and swing the ...
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2answers
111 views

Intercept of 2 moving objects at constant acceleration

I have to make a simulation in which a guided missile has to hit an incoming enemy missile.The enemy missile "T" is the one which has to be intercepted and is only affected by gravity, the guided ...
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1answer
75 views

What is the meaning of the integral of position?

Jerk, $j(t)=\dddot x(t)$, acceleration, $a(t)=\ddot x(t)$ and velocity, $v(t)=\dot x(t)$ are derivatives of position, $x(t)$. What is the meaning of the integral of position? For example, one could ...
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1answer
30 views

Air resistance and computing the maximum height

How do we compute the height of a ball when the velocity with which it was thrown up and the velocity with which it returned to my hand is given. The velocity with which it was thrown and with which ...
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2answers
245 views

Projectile motion - calculate landing angle

A projectile is launched at a $45^\circ$ angle, aiming for a target at a distance of 15 feet away from, and $2$ feet below the starting position. I'm looking for equations to determine: The ...
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1answer
108 views

Deriving the equation of motion for a rigid system

I want to derive equation of motion for the system shown in picture. How do I choose a generalized coordinate in order to calculate kinetic and potential energy of the system? I need the ...
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1answer
45 views

Velocity-time-distance problem

In my book the formula for the $y$-component of velocity during the upward projectile motion is given: $$V_y=V_{iy}-gt$$ and next to it the formula for $y$-component of velocity during the downward ...
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4answers
123 views

Force required to send ball in set trajectory

If I have a desired 2D trajectory where I know the desired speed of my ball and desired path, and a ball that starts at (x=0,y=0), how can I calculate the required force / point at which the force ...
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0answers
57 views

How to calculate the equations of motion for a dipole in an electric field in three dimensions

I'm having trouble modelling a system, which I thought would be simple but has turned out to be quite complicated. The system is a charged sphere in an oscillating three dimensional electric field. ...
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2answers
111 views

Spring and pendulum massive bob trajectory? [closed]

This is essentially a better formatted version of this question which was put on hold (also by myself), mainly for being a HW&E question without any research effort by the OP and poor formatting. ...
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1answer
54 views

Force required to rotate a rod around an axis [closed]

The problem I'm trying to solve is: How much force, momentarily applied to the rod, is required to rotate it around an axis by a given degree? Assuming there is friction applied at the axis (...
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0answers
51 views

Find the Kinematic degrees of freedom of the following contraption

In the above mechanism it is required to find the generalized coordinates to write equation of motion of the MDOF system. I just want to ask how do we actually approach such a problem? How to identify ...
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0answers
13 views

Calculate distance with variable acceleration [duplicate]

I know the time and I know the force that acts horizontally on a particle. The problem is that the force is F=k(D-V), where k and D are constants. So at the beginning where the particle has zero ...
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0answers
47 views

Elastic Plastic with Kinematic Hardening Material Model

I have a model which calculates the rate of deformation tensor using the Green-Lagrange strain rate, the material velocity gradient and the gradient of deformation tensor. $$\bar{\bar{D}} = \bar{\...
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2answers
47 views

In terms of forces and kinematics, why does a projectile, thrown forwards, bounce forwards?

I'm curious to know why a tennis ball bounces forwards after it has made contact with the ground considering I throw it forwards and downwards at the ground. I understand that is bounces up because ...
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4answers
248 views

Why the round trip instead collision time?

From Newton's second law, the $\Delta t$ is defined as the collision time, but why in this case, it can be assumed to be the value of time between successive collisions on 1 wall? If I have an ...
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2answers
126 views

What happens when two bodies collide in a dynamics point of view?

I'm a high school student learning about energy and momentum. What confuses me is the things with elastic and inelastic collisions. I completely (in my opinion) understand those concepts in energy ...
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1answer
144 views

Conservation of mechanical energy isn't giving me the right answer? [closed]

I have been trying to solve this question: You are working for a shipping company. Your job is to stand at the bottom of an 8.0 m long ramp that is inclined at 37 degrees above the horizontal. You ...
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1answer
84 views

finding velocity along a curve with kinematic equations using time

(i'm "not" looking for coding help. i need help setting up the math.) i'm writing a program for a physics class to find the velocity of an object across a random curve. where the only force acting on ...
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3answers
393 views

How to prove the average velocity formula without calculus

I often see the formula: $$ \overline v = \frac {v + v_0}{2} $$ in physics textbooks, to describe the average velocity for an object moving with constant acceleration. This formula is often ...
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1answer
45 views

Why trajectories approach to origin tangent to the slower direction?

I am reading non-linear dynamics from Strogartz. Suppose, I have two solutions of a non linear system: $x(t) = x_0e^{at}$ and $y(t) = y_0e^{-t}$, where $a\in \mathbb{R}$. Now it is clear that,for $a&...
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2answers
164 views

Elastic collision between two circles [duplicate]

I am trying to calculate the final velocities of two equal mass 2-dimensional circles after an elastic collision. I have tried to figure it out using formulas I know from high school physics, but ...
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2answers
46 views

A drop falling in the condensed air

A drop is falling in humid air with air resistance equal $F_r = - \alpha v^2$. In $t = 0$ the drop is ideally spherical, $h$ above the ground, has mass $m_0$ and velocity $v_0 = 0$. What mass and ...
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1answer
39 views

Find the height and the velocity of the object [closed]

A bolt is detached from the lower part of an elevator cabin that is ascending with velocity 6meters/second and for 3 seconds comes to the point from where the elevator started to ascend. Find: in ...
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1answer
25 views

Coefficient of restitution belongs to kinetics and not to kinematics?Reason

The Coefficient of restitution is defined as $$e=\frac{v_2-v_1}{u_1-u_2}$$ $$v_2\to \text{final velocity body 2}$$ $$v_1\to \text{final vel of body 1}$$ $$u_1\to\text{initial vel of body 1}$$ $$u_2\...
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2answers
50 views

Rocket altitude [duplicate]

I have a model rocket I'm planning to launch. I heard from someone that you can calculate the altitude by timing the rocket from the time it takes off to the time it lands. Does anyone know how to do ...
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3answers
151 views

Can a particle have no instantaneous velocity at all points of the path taken but a finite average velocity?

I have a question on kinematics. Say the path traced by a particle is given by a Koch curve or Koch snowflake. Now consider the particle starts from some arbitrary point $A$ on the curve and ...
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1answer
83 views

A fast object (0.8c) getting overtaken by another fast object (0.9c): why don't times agree?

I'm trying to work on an exercise in Wolfgang Rindler's book "Introduction to Special Relativity" and I'm stuck on the following exercise: Two particles move along the x-axis of S at velocities 0....
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2answers
51 views

Finding time when acceleration is not constant

First of all, I'm sorry if this is an ignorant question, but it is for a personal project and its been bothering me. Let's say you want to accelerate in you car for some amount of time, then let off ...
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1answer
84 views

Special Relativity Kinematics Problem with My Wrong Solution [closed]

You are traveling toward a large fixed mirror at a constant relative speed 0.20 c0 . At t = 0, when the mirror is a distance d from you, you emit a light pulse from a lantern and then detect the ...
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2answers
73 views

Experimentally measuring a sphere's moment of inertia

I'm a freshman in Physics and I'd like to design an experiment to measure a sphere's moment of inertia except, well, I'm not very familiar with the concept beyond the formulas it comes with as it was ...
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2answers
126 views

Does really a spring compresses placed between two blocks when one block is given force on a frictionless surface?

When Spring is placed between two bodies on a frictionless surface it gets compressed when one block is given kinetic energy as told by my physics teacher. But it should not compress as there's no ...
0
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1answer
42 views

Formula - Bounce height with respect to time

I'm trying to graph a bounce with respect to time. I have these formulas: $\frac 12 mV_2^2 = mgH_2$ and $H_2 = \frac{1}{2} \frac{V_2^2}{g}$ I will have a series of $H(t)$ formulas as I know how to ...
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2answers
45 views

How can I calculate the change in velocity? [closed]

"A runner runs at 4 m/s on a circular track constantly. A and B are opposite points on the track, so A is the starting point and B is halfway around the track. Calculate his change in velocity from A ...
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1answer
58 views

Why can the ball travel at the same speed to the left like the toy car and at the same time travel vertically upwards? [closed]

Imagine a toy car travelling at constant speed to the left. Balls are projected vertically upward one at a time, at 1-second intervals. Edited question : Why is the ball travelling at the same ...
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0answers
36 views

Particle Disintegration Range of Angles (Landau& Lifshitz)

In the particle disintegration problem in the book by Landau and Lifshitz (pg 44 question 3), it is asked to find the range for $\theta=\theta_1+\theta_2$, where $\theta_1$ and $\theta_2$ are the ...
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0answers
13 views

Kinematic equations of a cascading particle decay

This paper discusses different measurable quantities that can be used to search for unknown particles at particle accelartors. For the following decay it introduces the invariant mass $m_{XY}$: It ...
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2answers
552 views

How much energy is needed to move an object in lossless environment?

How much energy is needed to move a 1 kg object for a distance of 1 meter horizontally in a constant speed (assuming no energy is wasted)? Does it matter what is the movement speed (assuming not zero)...
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1answer
237 views

Understanding rotational motion on a rough surface

I am having trouble gaining an intuitive understanding of rotational motion for an object rolling on rough surface, and I have a few questions regarding it. Let's say that there's a cylinder that ...
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5answers
338 views

Pushing down on the gas pedal of a car a good example of jerk?

I'm trying to think of the clearest examples to demonstrate the concept of jerk to a layman. Ignoring drag and making other reasonable assumptions (friction is conveniently there to only allow you to ...
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1answer
38 views

Trying to find out how to calculate how fast something moves from the force [closed]

In our introductory physics class (8th grade) I/we would like to find out how fast a piece of paper needs to be moving to break a chopstick. [Similar to putting a straw through a potato] We will be ...
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2answers
93 views

Obtaining Velocity from Acceleration

I'm following a research paper (PDF via RG), part of which is about using the accelerometer of a smartphone to assist the user's positioning via WLAN. Accelerometer is used to determine if the user ...