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May
1
comment Finding $\theta$ at any point in time
Use the equations of motion with the following quantities: $$\begin{align} \sum \vec{F} & = \begin{pmatrix} F_x \\ F_y \\ 0 \end{pmatrix} & \sum \vec{M}_A & = \begin{pmatrix} 0 \\ 0 \\ \tau \end{pmatrix} \\ \vec{a}_A & = \begin{pmatrix} \ddot{x} \\ 0 \\ 0 \end{pmatrix} & \vec{\alpha} & = \begin{pmatrix} 0 \\ 0 \\ \ddot{\theta} \end{pmatrix} \\ \vec{c} & = \begin{pmatrix} \ell \sin\theta \\ -\ell \cos\theta \\ 0 \end{pmatrix} & \vec{\omega} & = \begin{pmatrix}0 \\ 0 \\ \dot{\omega} \end{pmatrix} \\ I_C & = \begin{vmatrix} & & 0 \\ & & 0 \\ 0 & 0 & I_{zz} \end{vmatrix} \end{align} $$
Apr
30
answered Momentum of a rack and pinion gear system excited by a time variant force
Apr
30
comment Spring pendulum system
Welcome to Physics. What is your question?
Apr
29
comment Rotation of a vector
The direction of $(1,2,3)$ is the same as the direction of $(2,4,6)$ where all the components are scaled by 2.
Apr
29
answered Rotation of a vector
Apr
29
comment Rotation of a vector
Not if the components are all scaled by the same amount. The component change but the direction is does not.
Apr
29
answered Net force equal to mass multiplied by acceleration of centre of mass
Apr
29
answered Rigid Body Dynamics - Calculating Rotation of an Object
Apr
29
comment Newton's 2nd law for rotation (accelerated rolling and inertial frame of reference)
This question has been answered before in here multiple times. It is hard to find past questions unless you use the right keywords.
Apr
29
comment Newton's 2nd law for rotation (accelerated rolling and inertial frame of reference)
Possible duplicate of Why is the center of mass frame always used in rigid body dynamics?
Apr
28
answered What is the physical meaning of reduced mass?
Apr
27
comment Can't identify static and kinetic friction regions
Are you pulling or pushing on the specimens ??
Apr
27
comment Can't identify static and kinetic friction regions
To set the part in motion at an infinitesimal time you are looking at a frictional impulse being applied. I doubt you can measure this.
Apr
27
comment Can't identify static and kinetic friction regions
Because parts are not rigid it is possible the movement gets initiated by a strain wave along the material. For steel this wave travels at 5000 m/s and so if you have a 1m long specimen the time to unstick is in the order of 1/5000-th of a second. So yes, it is entirely reasonable you are missing it.
Apr
27
comment Can't identify static and kinetic friction regions
How are you measuring friction? Static friction may occur over such small time period that you might not see it.
Apr
27
comment Rotational Dynamics Question
What is your question? This appears to be a question someone asked of you to answer.
Apr
26
comment How to calculate torque required?
Do you know the mass moment of inertia of the pulley, motor and any gear-train attached to it? The dynamics of the system might depend on this a lot.
Apr
26
comment How to calculate torque required?
This answer would be much better with math formatting. Enclose expressions in dollar signs$...$ for inline or $$...$$ for paragraph style. Then use \frac{a}{b} for fractions like $\frac{a}{b}$.
Apr
26
answered When only part of the surface an object is in contact with has friction, what is the normal force I should use?
Apr
25
comment Why is the Plane progressive wave equation $y= a\sin (kx-wt)$ for positive direction of x-axis?
Find for which $x$ the argument $kx-\omega t$ is zero? It will be $x = \text{(positive)} \,t$