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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0answers
19 views

SONAR - submarine speed detection

A submarine can use sonar (sound traveling through water) to determine its distance from other objects. The time between the emission of a sound pulse (a “ping”) and the detection of its echo can be ...
0
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1answer
47 views

How to calculate angular velocity given constant tangential acceleration? [on hold]

A car starts moving in a circle with a radius of $200 \text{ m}$. It has a constant tangential acceleration of $1{\text{m}\over {\text{s}}^{2}}$. a. What is the angular acceleration? b. What is the ...
0
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0answers
22 views

Help with inclined slope motion? [on hold]

I have this question (5ii) and I was wondering why this wouldn't work, why can't I solve for acceleration using $v^{2}-u^{2}/2s$=$a$ then solve for $t$? I obviously have to resolve and use $p=fv$ but ...
3
votes
3answers
59 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?
0
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1answer
25 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 ...
1
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1answer
30 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 ...
0
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0answers
11 views

Find out average speed [closed]

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
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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
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0answers
29 views

Exam preperation [closed]

I really need your help preparing for my upcoming exam. here are my questions:
0
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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 $(1,0)$?
0
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2answers
32 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
35 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 ...
2
votes
3answers
487 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
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1answer
71 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
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3answers
43 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
808 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 ...
4
votes
4answers
531 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?
0
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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
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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 ...
0
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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
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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
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1answer
38 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 ...
1
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0answers
111 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
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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 ...
-1
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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 ...
1
vote
2answers
137 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
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2answers
31 views

Average acceleration versus instantaneous acceleration

Does instantaneous acceleration also changes when direction of velocity changes. I know average acceleration does change.
1
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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. ...
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 ...
1
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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 ...
0
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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
999 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 ...
1
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0answers
27 views

How to solve Kinematics: two objects meeting in the air

A water balloon is dropped from the top of a 200m high tower. An alert archer at the base of the tower sees the balloon being dropped, waits for 5s, then shoots an arrow at 40m/s straight up towards ...
0
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2answers
28 views

Can Theta be greater than 360 degrees in this equation?

I have a quick question regarding Rotational Motion. I understand the equation x = r (theta) and I know that theta represents the Angular Displacement for a circle but what if the linear distance ...
1
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2answers
61 views

Confusing, can a motor on a moving disc stop the disc?

I've been troubled trying to solve this problem. If a motor is fixed on a moving rotating disc and the motor's rotor has another disc attached to it. What would happen if we attached the motor's ...
12
votes
3answers
2k views

How does anything move? [duplicate]

So in order for two things $A$ and $B$ to move apart, for example, relative to each other, $B$ can be set into motion away from $A$. This means that we have to increase $B$'s velocity and therefore ...
0
votes
1answer
36 views

Constrained Motion of Connected Particles, Small Calculation Question

I am looking at this sample problem from Meriam Kraige - Engineering Mechanics Dynamics: When I do the differentiation, I end up with $\large -2\dot y+\frac{x}{\sqrt{x^2+h^2}}$ Where is the $\dot ...
11
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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" ...
2
votes
4answers
1k views

Is there a formula that gives the position of an object depending on the time, but which doesn't allow the object to surpass the speed of light?

I have found these two formulas: $v = at + v_0$ $x = \frac{1}{2}at^2 + v_0t + x_0$ a is the acceleration v is the velocity x is the position t is the time $v_0$ is the initial velocity $x_0$ is ...
0
votes
3answers
85 views

Why is the range of a projectile proportional to the square of the initial velocity?

I was watching the MIT lecture about projectile motion and the lecturer asked why $$D=\frac{(v_0)^2\sin(2\alpha)}{g}$$ Why is it $(V_0)^2$ not $V_0$? It is a hypothetical question i know that the ...
0
votes
1answer
55 views

Is this movement possible?

My friend and I were arguing over some random facebook shared video. On this video, one guy throws up a rotating stick then, while it rotates on air, he kicks through it. Is it even possible? Or is it ...
1
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0answers
27 views

Projectile Motion [closed]

I've spent some time pondering the answer to this equation, without any success. A cannon is arranged to fire projectiles, with initial speed $v_0$, directly up the face of a hill of elevation angle ...
-2
votes
1answer
36 views

Find the average speed and velocity of the object [closed]

An object travels 11 m north and then turns around and travels 25 m south. If the total time of travel is 52 s what is the average speed and velocity of the object. I used the formula I was told ...
1
vote
2answers
95 views

Do rotation matrices rotate about inertial or body angles? [closed]

I have Yaw, pitch, and roll angles in that order (Euler 321) to apply to a body reference frame in cartesian coordinate system. I want to know what the body reference frame vector coordinates are ...
-1
votes
1answer
70 views

A particle is constrained to move around the unit circle in the xy plane according to (x,y,z) = (cos(t^2),sin(t^2),0) t >= 0 [closed]

A particle is constrained to move around the unit circle in the xy plane according to (x,y,z) = (cos(t^2),sin(t^2),0) t >= 0 At what point should the particle be released to hit a target of (2,0,0)? ...
2
votes
1answer
138 views

Insight into Torricelli's Equation ($v^2=u^2+2as$) [closed]

Torricelli's Equation ($v^2=u^2+2as$) is usually presented as the particular formulation of the SUVAT system which doesn't involve t. It is derived from the others using some (perhaps well-motivated) ...