Dynamics: Absolute and Relative Acceleration in Plane Motion

[Drew Davison]

Homework Statement

A force P is applied to the rod which rests on a horizontal table. The following accelerations are produced. a_A= 3.6m/s² to the right, α of the rod = 6 rad/s² CCW. Determine the acceleration of point G and B

Homework Equations

a_G=a_A+a_G/A
a_G=a_A+[(a_G/A)tangential + (a_G/Anormal)]
a_G=a_A+[(α X r_G/A) + ( ω² * r_G/A)]

The Attempt at a Solution

So I tried to solve the problem and quickly found that there is no way to solve for angular acceleration (ω). Looking at the solution they completely leave out the normal component of acceleration to solve for the acceleration at G and A. They just plug in values for acceleration at A, angular acceleration and distance from A to G.

I can't figure out why there is no normal component of acceleration in this problem.
Any help?
Thanks!

 

[haruspex]

is there a force parallel to AG?

 

[Drew Davison]

No only the forces that are show. The evaluation of the question only involves the accelerations

 

[SammyS]

Homework Statement

A force P is applied to the rod which rests on a horizontal table. The following accelerations are produced. a_A= 3.6m/s² to the right, α of the rod = 6 rad/s² CCW. Determine the acceleration of point G and B

Homework Equations

a_G=a_A+a_G/A
a_G=a_A+[(a_G/A)tangential + (a_G/Anormal)]
a_G=a_A+[(α X r_G/A) + ( ω² * r_G/A)]

The Attempt at a Solution

So I tried to solve the problem and quickly found that there is no way to solve for angular acceleration (ω). Looking at the solution they completely leave out the normal component of acceleration to solve for the acceleration at G and A. They just plug in values for acceleration at A, angular acceleration and distance from A to G.

I can't figure out why there is no normal component of acceleration in this problem.
Any help?
Thanks!

Do you know how to work with the center of mass ?

 

[haruspex]

No only the forces that are show. The evaluation of the question only involves the accelerations

Then why should there be an acceleration in that direction?