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-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 ...
Ulshy's user avatar
  • 69
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 ...
user146290's user avatar
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 ...
user57467's user avatar
  • 478
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 ...
Stanley's user avatar
  • 21
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^...
Shinnaaan's user avatar
  • 1,357
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 ...
Elias K.'s user avatar
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 ...
Kjell De Mars's user avatar
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 ...
Utkarsh's user avatar
  • 51
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 ...
user avatar
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 ...
Javier TG's user avatar
  • 125
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 ...
aa bb's user avatar
  • 21
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 $a$. ...
madness's user avatar
  • 1,179
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 = ...
thetrueembodimentofstupidity's user avatar
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 ...
Arjun Inamdar's user avatar
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 ...
Chern-Simons's user avatar
  • 1,047
-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 ...
Anshuman Bharadwaj's user avatar
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, ...
R S's user avatar
  • 349
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 ...
Mysterio's user avatar
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 ...
Josh's user avatar
  • 13
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 ...
Deschele Schilder's user avatar
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 ...
satan 29's user avatar
  • 1,295
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 $a_t$ ...
Curious 's user avatar
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?
ah123's user avatar
  • 331
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 ...
Fluidized Pigeon Reactor's user avatar
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 ...
Majid ALZADJALI's user avatar
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 ...
Adrian's user avatar
  • 1
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. ...
Random's user avatar
  • 88
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 ...
Tony's user avatar
  • 132
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 ...
sarthak-ag's user avatar
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?)
Pranav's user avatar
  • 1

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