All Questions
Tagged with rotational-kinematics acceleration
55
questions
-2
votes
2
answers
98
views
Why does $\vec{a}=\vec{\omega}\times \vec{r}$ as well as the velocity does?
Today I came in class and in one of the problems the teacher used $\vec{a}=\vec{\omega}\times \vec{r}$ which made me very confused because I don't know where it comes from, it seems pulled out of thin ...
1
vote
1
answer
159
views
How to compute linear acceleration in 3D from change in roll, pitch and yaw angles?
We know that if a body is rotating only about $z$-axis along a circle of radius $R$ with an angular rate of $\omega$, then the acceleration of the body in 3D is $a = [0.0\ \ \omega^2R \ \ 0.0]$. Now ...
0
votes
1
answer
51
views
Does a rotating body resist acceleration in a direction that is perpendicular to the direction of the rotation of the body?
I would like to know if a rotating body resists acceleration in a direction that is perpendicular to the direction of the rotation of the body.
Say for example there is a bicycle wheel with a tire on ...
2
votes
1
answer
69
views
(Circular motion) Acceleration is given, so why asked for more? [closed]
The full question is below.
A car starts from rest and moves around a circular track of radius $32.0\,\text m$. Its speed increases at the constant rate of $0.500\,\text{m/s}^2$.
(a) What is the ...
0
votes
2
answers
328
views
Does a simple pendulum have some radial acceleration at its extreme positions where its speed becomes zero?
Suppose we have a simple pendulum swinging between two extreme positions. At the extreme position its speed becomes zero. As per this reason can I say that at extreme positions radial acceleration (v^...
1
vote
2
answers
277
views
Is accelerated rolling with slipping possible?
I have a conceptual question regarding the following tasks. Two cylinders with different coefficients of friction are rolling down a inclined plane, thus accelerating. According to the task, due to ...
0
votes
2
answers
706
views
What is the real difference between radial and tangential acceleration?
So in my physics coursebook there are two different kinds of derivation of $\frac{dv}{dt}$ of a particle rotating in a circle. Most of you will know these, they are what is called centripetal/radial ...
0
votes
1
answer
579
views
I am very confused about net acceleration and angular acceleration in circular motion [closed]
I have seen in many places that angular acceleration can be zero but net acceleration can't be zero in circular motion. I want to know whose components are tangential and radial acceleration (net or ...
0
votes
2
answers
51
views
Can a particle make a turn in space without accelerating? Does the size of the turn it makes, make a difference?
Is it possible for a particle to have angular velocity but no angular acceleration? Even if the angular velocity does not change, does there always need to be a centripetal / centrifugal acceleration ...
0
votes
1
answer
731
views
Angular acceleration related to a time dependent rotation matrix $R(t)$
Let the orientation of a coordinate frame $\{b\}$ w.r.t. a static coordinate frame $\{a\}$ be expressed by a rotation matrix $R_{ab}\in SO(3)$ whose columns represent the coordinates of the unitary ...
2
votes
1
answer
39
views
Finding Average Acceleration with only given angle [closed]
A car enters a curve in the road with a speed of 32 m/s and emerges from this curve 4 s later with the same speed. However, the direction of the velocity changes by 150 degrees during this time.
What ...
1
vote
2
answers
99
views
Use of net acceleration in circular motion
We know there are two types of accelaration in circular motion, one is centripetal acceleration and the other one is tangential acceleration. The resultant of these two is the net acceleration $a$. ...
4
votes
4
answers
427
views
Centripetal force equation doubt
In a centrifuge, $a_c$ should be constant. If $m$ increases, the $r$ will increase in order to maintain a constant $a_c$.
Constant centrieptal acceleration is given by
$a_c={ v^2 \over r}$
and $a_c = ...
1
vote
5
answers
583
views
Confusion about acceleration in rotating without slipping
We know that if there is a flat surface with friction, a ball rolling without slipping will conserve its energy, as friction does no work on the ball.
$$\Delta E = 0 $$
Because kinetic energy is ...
1
vote
3
answers
186
views
Definition of torque in the (possibly accelerating) centre of mass frame
My lecture note states that the torque in the centre of mass frame ($O^*$) of a rigid body is: $$\bf{G^*}=\sum \bf{r^* \times F}$$
where $\bf{F}$ denotes the real force that is producing the torque
...
-1
votes
2
answers
724
views
In rotational motion, why $a = rα$?
The formula of torque is given by $$τ= F*r = Iα,$$ while solving some questions I came across a question of rotating pulley where these two formulas were equated to find value of $α$. How $a=rα$? a ...
13
votes
12
answers
6k
views
Why is acceleration directed inward when an object rotates in a circle?
Somebody (in a video about physics) said that acceleration goes in if you would rotate a ball on a rope around yourself.
The other man (ex Navy SEAL, on YouTube too) said that obviously it goes out, ...
0
votes
3
answers
821
views
Condition for pure translational motion
Q:If we know that the acceleration vectors of all points of the rigid body are equal to each other at all points of time, can we conclude that the body is undergoing pure translational motion?
I ...
1
vote
1
answer
104
views
Wheel slips and weight
With rainy season starting, I have been thinking about traction and have a question:
Question: If two identical vehicles, one of mass $m$ and the other of mass $2m$ are starting from rest with equal ...
2
votes
1
answer
125
views
About the water surface in a accelerated cylinder
After I woke up this morning while sitting at our table I looked at a plastic bottle of cola lying on the floor. Please, don't think it's a mess out here. It just lay there. I put it nicely back on ...
6
votes
5
answers
1k
views
Finding accelerations using Instantaneous axis of rotation
Disclaimer: I present a question which is homework-like, However it is simply to demonstrate an example. I only wish to clarify one thing, that is the validity of the IAR in determining the ...
5
votes
3
answers
2k
views
Does tangential acceleration change with radius? [closed]
Do tangential velocity and tangential acceleration change with radius (change of radius on the same object)?
For example consider a spinning disk. Does the equation $$a_t = \alpha R$$ (where $a_t$ ...
1
vote
3
answers
595
views
Angular Acceleration v. Centripetal Acceleration
What is the difference between angular acceleration and centripetal acceleration? Don't they both apply to circular motion?
1
vote
1
answer
371
views
Acceleration of a Point on the Edge on a Rolling Cylinder
Consider a cylinder with radius $R$ rolling without slipping to the right. The center of mass is rolling with a velocity of $v$. Consider the left most point, $p$, on the cylinder. What is the ...
0
votes
1
answer
446
views
Calculating acceleration of an object using $x$, $y$ and $z$ coordinates [closed]
I have x, y and z coordinates for a test I had carried out for a tool. I had an accelerometer installed on the tool and I used two types of motion to move the tool, rotation and translation. Right now ...
0
votes
0
answers
65
views
Does acceleration of the rim mean just tangential or both tangential and centripetal acceleration?
On my physics homework, the problem specifies that the acceleration of the rim of a flywheel can't exceed 100g. Does this mean that the tangential acceleration only, or the sum of the tangential and ...
2
votes
3
answers
113
views
What is wrong with this reasoning?
Suppose a particle is rotating about a point at a distance $r$, then since $r$ is constant $\frac{\text dr}{\text dt}=0$ so the component of velocity along the position vector should be zero. ...
1
vote
2
answers
3k
views
Find the time when tangential acceleration is equal to radial acceleration [closed]
A particle begins to move along a circular path of radius R with a constant magnitude tangential acceleration of $a_t$. After time $t$ it's the centripetal acceleration is equal in magnitude to ...
0
votes
2
answers
235
views
Intuition for formula of tangential component of acceleration in general curvillinear motion
In certain problems of plane motion, the position of the particle P is
defined by its polar coordinates $r$ and $\theta$. It is then convenient to resolve the velocity and acceleration of the particle ...
0
votes
1
answer
133
views
When a body completes one revolution around a circular path will its acceleration be 0?
When a body is moving in a circular motion the acceleration keeps changing, will it be zero when it comes back to the same point it started from(will the average acceleration be 0?)