# Angular acceleration x radius= Acceleration of center of mass ?

For a rotating body,
(angular acceleration x radius)= Acceleration of center of mass ?

But a rotating body can have angular acc. even if it is not translating. what is wrong?

no no no........... angular acc. x radius = the linear acc. of a point on the body , ie the tangential velociti of that point with respect to the centre of mass

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the point is moving around the body with a speed= R x α
where α= angular acceleration

Hi Aakash...

The correct relationship for a point on a rotating body is

atan = αr where ,

atan=tangential acceleration of the point with respect to center of the axis

α = angular acceleration of the rotating body

r= distance between the point and the center of the axis

For a rotating body,
(angular acceleration x radius)= Acceleration of center of mass ?

But a rotating body can have angular acc. even if it is not translating. what is wrong?

The relationship acm = αr is a constraint which is sometimes obtained in cases when a body is rotating as well as translating.

For eg. a sphere rolling without slipping on floor .

Hi Aakash...

The correct relationship for a point on a rotating body is

atan = αr where ,

atan=tangential acceleration of the point with respect to center of the axis

α = angular acceleration of the rotating body

r= distance between the point and the center of the axis

The relationship acm = αr is a constraint which is sometimes obtained in cases when a body is rotating as well as translating.

For eg. a sphere rolling without slipping on floor .

i have told the same........ i have told the same........ Your language is sloppy and inaccurate .

no no no........... angular acc. x radius = the linear acc. of a point on the body , ie the tangential velociti of that point with respect to the centre of mass

The item in red should be acceleration.

Again ,instead of center of mass,you should have used center of rotation.

the point is moving around the body with a speed= R x α
where α= angular acceleration

That doesn't make any sense . Neither the point is moving around the body ,nor is speed equal to R x α

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thanks.