Questions tagged [kinematics]

For questions on the motion of points, bodies (objects), and systems of bodies (groups of objects) without considering the mass of each or the forces that caused the motion.

254 questions
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3 particles A,B and C are situated at the vertices..

I had this question "3 particles A,B and C are situated at the vertices of an equilateral triangle ABC of side d at t=0. Each particle moves with a constant speed v. A always has its velocity along ...
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Angular velocity of a unit vector given spherical angles

Consider the unit vector of $$\check{n} = \begin{bmatrix} \sin \phi \sin\gamma \\ \cos \phi\\ \sin \phi \cos\gamma \end{bmatrix} \, . \tag{1}$$ ...
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velocity and acceleration in a parabola

A particle moves with constant speed along a parabola of equation $y^{2}=2px$ with $p=constant$. I want to find its velocity and acceleration vector. Since the velocity magnitude is constant I know ...
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How to graph the motion of a projectile?

Suppose I have a projectile, fired at angle $\theta$, with velocity $v_0$, assuming it's only acted upon by gravity. How can I find an equation to enable me to plot the motion (vertical height against ...
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Swimming to a Boat [closed]

A boat is travelling on a bearing of $α=60^\circ$ at a constant speed $u=3.0$ $m/s$. A man is swimming at a constant speed $v$ in order to reach the boat from a point a distance $l=100\ m$ due east ...
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Find acceleration of a particle when given a velocity function in terms of displacement.

Particle B moves such that its velocity $v\>ms^{-1}$ is related to its displacement $s\>$m, by the equation $v(s)=arcsin(\sqrt{s})$. Find the acceleration of particle B when $s=0.1$m. My ...
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kinematics .. how to solve this question. shouldn't acceleration be 0 when velocity is 0?

a particle moves in a straight line so that , t s after passing through a fixed pointO , its velocity, v m/s, is given by v=2t-11-(6/(t+1)). find the acceleration of the particle when it is at ...
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Showing that $x(t)=at^2$, $y(t)=vt-at^2$ parameterizes a parabola

Solving a physics problem I obtained following motion equations $$x(t) = at^2$$ $$y(t) = vt - a t^2$$ And I want to determine what type of curve is it on the interval of $\left<0,v\right>$. ...
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Theoretical mechanics - Inverse Kinematicss

On theoretical mechanics essay at the university, I have stumbled in the issue below: Given $\textbf{u}^T \textbf{D}(\mathbf{\theta}, \alpha)\textbf{v}(\textbf{d}) = \textbf{m}(\textbf{d})$, find out ...
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What is the initial acceleration of three particle at the vertex of an equilateral triangle moving towards its neighbor?

I came across this question which, asks, 3 particles, at the corner of an equilateral triangle of side s, start moving with constant speed v, such that each always heads directly towards its ...
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a cyclist travels 30 km in one hour [duplicate]

a cyclist travels 30 km in one hour 1) Demonstrate that there is an interval of 10 minutes such that the cyclist has traveled 5 Km 2) Is there always a time interval of 40 minutes during which he ...
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Physics force system find acceleration

Given this setup, how far does the book slide? This is a fairly basic kinematics problem once you have acceleration, which you can get with application of Newton's 1st and 2nd laws. Which is what I ...
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How can i solve for time in fourth kinematic formula? [closed]

The fourth kinematic formula says that; $\Delta x = vt + \frac{1}{2}at^2$ Where: $\Delta x =$ Displacement $v =$ Initial velocity $t =$ Time $a =$ Acceleration (Note that acceleration needs to ...
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How can I find the magnitude of the acceleration in this $2$-D motion kinematic equation?

Can someone help me plug in the correct variables for this $2$-D motion problem? So the problem is: A puck moves $2.35 \frac{m}{s}$ in a $-22.0^\circ$ direction. A hockey stick pushes it for $0.215$ ...
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Get acceleration from distance and speed [closed]

I want to know how fast an object with the speed s1 (2.77m/s) would have to deccelarate to reach a speed s2 (0m/s) within a certain distance d (2.35m). With a formula for that I could go on to ...
Let's Imagine such a situation. A man is walking for the first hour with a speed of $4km/h$. The next hour he is jogging, with the speed of $9km/h$ Finally, after two hours, he starts to run, with the ...