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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5
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5answers
348 views

Infinite series of derivatives of position when starting from rest

Suppose you have an object with zero for the value of all the derivatives of position. In order to get the object moving you would need to increase the value of the velocity from zero to some finite ...
0
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1answer
22 views

Computing Acceleration in mass and pulley system using conservation of energy

I have a question in which a multiple pulley and mass system is being analysed. I can compute accelerations and Tension without any issue using newtons second law. However I am asked to use ...
3
votes
3answers
50 views

Does my (too low) tire pressure, affect the speedometer of my car?

Does my (too low) tire pressure, affect the speedometer of my car? How big is this effect?
3
votes
1answer
248 views

Acceleration: A ball sliding down the inside of a semicircular bowl

Edit: To clarify, this is a homework question. But I couldn't care less about getting the answer to this specific question as it's not even assigned yet. It looks interesting and I want to understand ...
41
votes
5answers
14k views

How effective is speeding?

At a simple level, speeding in a car attempts to minimize the time required to travel a distance by utilizing the basic relationship: $$d=st$$ So for a given distance, time should be inversely ...
1
vote
1answer
29 views

What is the position as a function of time for a mass falling down a cycloid curve?

In the brachistochrone problem and in the tautochrone problem it is easy to see that a cycloid is the curve that satisfies both problems. If we consider $x$ the horizontal axis and $y$ the vertical ...
7
votes
1answer
265 views

Is it possible to determine particles' velocities from their crossings on a ring?

2 particles are constrained to move in a ring. Both particles begin moving at $t=0$ from $p=0$, each particle moving in the opposite direction of the other. It is known that they are moving at ...
0
votes
0answers
11 views

Find out average speed [on hold]

Akshit drove his car with speed 20km/h while going to his college. When he returned to his home along the same route, the speed of the car is 30km/h. Calculate the average speed of his car through ...
0
votes
1answer
31 views

Six particles at the corners of a regular hexagon of side $a$ move at a constant speed $v$ [duplicate]

Each particle maintains a direction towards the particle at the next corner. Calculate the time the particles will take to meet each other. When the particles move with same speed,how can they ever ...
0
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2answers
13 views

Net Force On An Object

If 5 different forces are acting on an object in the same direction, is it possible for the net force to equal 0? Could Friction or Gravity make this possible? If so then how?
0
votes
0answers
28 views

Position, Velocity and Acceleration in a Forced Harmonic Oscillator [closed]

The problem is the following: An particle has a potential energy enough so that the 0.2Kg particle moves up 0.45m and has a displacement of 1.78m. The particle presents a period of 0.1242s, and is ...
-4
votes
0answers
28 views

Exam preperation [closed]

I really need your help preparing for my upcoming exam. here are my questions:
0
votes
0answers
37 views

A fly travelling on a Cartesian plane [closed]

Beginning at point $(-1,0)$, a fly travels across the semicircle defined by $y=\sqrt{1-x^2}$. Its acceleration is given by $a=(t-1)^3+1$. How long does it take the fly to arrive at point $(1,0)$?
2
votes
3answers
481 views

Object moving in a circular path without accelerating

A train is moving with a constant speed on a straight portion of track. Then, it encounters a curve in the tracks, and goes along the curve. However, it does not change the magnitude of acceleration ...
0
votes
2answers
30 views

What theories or formulas are involved with velocity

What theories or formulas are involved or can be added as background information in an experiment that sees a small toy car roll freely down an incline where the surface area is altered to cause more ...
0
votes
1answer
34 views

Kinematics - When projectile lands at an angle

Question: You are watching an archery tournament when you start wondering how fast an arrow is shot from the bow. Remembering your physics, you ask one of the archers to shoot an arrow parallel to ...
0
votes
1answer
60 views

What factors affect the velocity of an object moving down an inclined plane?

If you have a small toy car rolling down an wooden plank, what factors would increase or decrease the velocity of said car. In the experiment my team originally stated that adding mass to the car ...
0
votes
3answers
42 views

How does $p=fv$ hold when $v=0$ and an engine is working?

Standard high school equations: Work = Force x Distance Power = Work / Time = Force x Distance / Time = Force x Velocity When a space rocket takes ...
3
votes
2answers
805 views

How can an object move from point A to point B?

If I was at point $A$ and I wanted to walk directly to point $B$, I would have to walk half way to point $B$, but before that I would have to walk half way to halfway to halfway to point $B$ and half ...
0
votes
2answers
2k views

Homework Question Transformation Energy [closed]

A $1400kg$ car is approaching the hill shown in the figure at $14.0m/s$ when it suddenly runs out of gas. What is the car's speed after coasting down the other side? I think I have to use this ...
-2
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0answers
40 views

Please help in this question [closed]

An object slides down frictionlessly from the top of a fixed straight slope of base 30cm.At least how long does it take for the object to slide down?
0
votes
1answer
76 views

How does angular momentum affect the trajectory of a projectile?

I am thinking about a football thrown in a very tight, very fast spinning spiral. If the football is thrown upwards at a high angle, is it possible for the football to not turn over at the top of its ...
1
vote
1answer
88 views

Magnitude of the average velocity vector (not the average speed)

Thank you ahead of time for taking to look at this. For this following problem we were given an answer however I am almost positive the given answer is wrong. It doesn't even make sense. So here is ...
1
vote
1answer
209 views

Shooting a bullet at a system of blocks [closed]

So, I made this question up myself.... and I'm curious about the answer. It requires only secondary-school-level knowledge of physics: You have a surface (ground) with a certain coefficient of ...
0
votes
2answers
156 views

Ball flying towards me - Newton's third law is violated?

I was trying to answer the question of the flying ball here on the basis of Newtons third law and Momentum conservation. Here is what I have tried. Lets take $m_1$ (the ball) hits $m_2$ (the man). ...
0
votes
1answer
37 views

Maximum Momentum of Neutral Pion

I'm considering the reaction $p + p \rightarrow p + p + \pi^0$. To find the maximum momentum that the $\pi^0$ can have after this reaction in the center-of-mass frame, what I am doing is assuming the ...
0
votes
2answers
468 views

Determine resultant velocity of an elastic particle-particle collision in 3d space

So I have two particles that have collided in 3 dimensional space. I want the particles to rebound off of each other in an elastic manner. How do I determine the resultant velocity vector if I know: ...
3
votes
2answers
240 views

Projectile motion maximum distance to origin

Is there an elegant or easy way to derive the maximum distance from the origin to a point of the parabola created by projectile motion (assume initial position is the origin)? Other than ...
4
votes
4answers
530 views

Is there any such thing as a change in acceleration (ex: 3 m/s/s/s)? [duplicate]

If there exists something like that, then in $distance/time/time/time$, how is it expressed?
1
vote
2answers
31 views

Average acceleration versus instantaneous acceleration

Does instantaneous acceleration also changes when direction of velocity changes. I know average acceleration does change.
0
votes
1answer
26 views

Modifying differential equations representing a projectile system to account for an arbitrary force

The following series of differential equations represents a projectile's path when solved (g=9.81): Here is some sample output from this system (with initial values x,y=0, v=1500, theta=1.33): I ...
0
votes
2answers
30 views

How to measure the range of a horizontal projectile?

For an experiment, I'm launching a projectile horizontally to determine the relationship between height and range. Pretty basic stuff. But I'm having trouble coming up with an effective way to measure ...
1
vote
0answers
110 views

Am I right in my understanding of angular motion?

Here is what I've understood about angular motion: If a force is applied at the center of mass of a rigid body, it will undergo pure translational motion. If a force is applied away from the center ...
0
votes
2answers
61 views

Why is there a contradiction in this Newton's equations of motion related question? [closed]

One second after being thrown straight down, an object is falling with a speed of 20 m/s. How much distance does the object travel in the first second? We took: $$v = 20\,{\rm m/s}$$ $$u = 0\,{\rm ...
1
vote
1answer
31 views

What is displacement time series?

For a car motion, I have time vector (starting from 0 to 40 with 0.1 increments) so that the time vector is something like $\begin{bmatrix}0&0.1&0.2&0.3&\ldots&40\end{bmatrix}$ and ...
0
votes
2answers
138 views

Animating an Acceleration Vector - Acceleration of object on a crested path in gravitational field

So I was reading in Chapter 3 of my textbook, Sears & Zemanksky's University Physics with Modern Physics by Young and Freedman, 13th Edition, and the discussion took us to a definition of the ...
1
vote
2answers
136 views

At what point does force stop translating an object and start purely rotating it? [duplicate]

At what point (or distance) from the axis of rotation, does force applied on a rigid body stop translating and purely rotating the body? Can such a point even exist? Does the body always have to ...
-1
votes
1answer
60 views

Throwing a basketball. What do I need to consider to hit a target? [closed]

This is a question that's been bugging me for some time now and the physics department at school is closed so yeah. Anywho, my question was, given a ball of mass .76, what forces would i have to ...
0
votes
0answers
17 views

Optimal “Blow up” Configuration

Suppose you have three balls glued together. Two are red and one is blue. The system of balls is blown up by an explosion of pure energy (that conserves the center of mass frame) exactly at the ...
0
votes
1answer
30 views

Relativistic Kinematics - 2-Body Particle Decay

Consider the scenario where a particle of mass $M$ decays into two lighter particles of mass $m_1$ and $m_2$. In the center of mass frame (i.e. $\mathbf{p}_1$ and $\mathbf{p}_2$, the momenta of the ...
8
votes
4answers
3k views

Static Friction - Only thing that can accelerate a train?

I'm a computer programmer that never studied physics in school and now it's coming back to bite me a bit in some of the stuff I'm being asked to program. I'm trying to self study some physics and ...
1
vote
3answers
54 views

How do these factors affect the free fall of objects?

Take an example of two balls of different masses being dropped from about 250 meters from the ground. How do the following factors affect free fall: Air resistance. Absence of air resistance. ...
2
votes
3answers
536 views

Does a heavy body move with the slightest force on a frictionless surface?

If I apply horizontal force on a body resting on the ground, my force will be opposed by the frictional force and the body will accelerate at the point where my force exceeds the force of friction = ...
0
votes
0answers
54 views

How does Zeno of Elea's argument on “motion” make sense? [duplicate]

Zeno of Elea (born c. 500 bce) argued so intensely about motion. In one of his arguments he claims – in simple language – "that it is impossible to slap somebody, since the hand first has to travel ...
0
votes
1answer
170 views

Circular motion - is average velocity enough to tell?

If I knew the exact value of constant centripetal force and the average velocity of an object travelling around a circle for time $t$, would that be enough information to determine the final positon ...
1
vote
0answers
46 views

Equivalence of delta functions when calculating decay rate [closed]

$\newcommand{\bs}{\boldsymbol}$ Hello, I'm currently working through the lecture notes of my Theoretical Particle Physics course, and there, we are calculating the decay rate of the following process ...
11
votes
2answers
1k views

Why collide a moving particle with a particle at rest, rather than two moving particles?

I was just reading some lecture notes about relativistic and quantum mechanics, and in the later part of this page the author demonstrates that any relativistic particle collision in the "lab" ...
0
votes
1answer
53 views

In circular motion, what's preventing me from calculating the circumference of the circle, dividing it by time to find the speed of the object?

There are equations to solve for the speed in circular motion. However, is there anything preventing me from calculating the circumference from the given radius, and then divide that over the time to ...
13
votes
2answers
996 views

In an electron-positron annihilation, in what direction are the photons released?

I read that, in an electron-positron annihilation, at least 2 photons are produced, because of the law of conservation of momentum. my question is: in what direction are those photons released? and ...
0
votes
1answer
69 views

Newtons 3rd law, on two opposing discs?

Assume a large disc at rest(bottom disc), and free to move. Above it is another disc(disc2) that's rotating, and a motor fixed on that large disc(bottom disc) as well, that's load is a disc rotating ...