Fall 2008 --
Purdue University -- West Lafayette, IN
Jan 28, 2008
Problem 5/153
Do we need to have 3 acceleration equations to solve this one after we find V_B and omega_AB? I am setting up something wrong because I keep getting zero for alpha_AD. Is that correct?
You don't need to find V_B. You just use the acceleration equation between A and B to find alpha_AD. Then use one last acceleration equation to find A_D.
The acceleration of B is only in the X direction, but you don't need to find it. You use the acceleration equation between A and B to find alpha_AD. There will be no component of acc_B in the j direction, which allows you to find alpha_AD
Please note that DAB is a single rigid body. The rigid body has only one angular velocity and one angular acceleration regardless of which two points that you use in the acceleration equations of the rigid body.
You don't need to find V_B. You just use the acceleration equation between A and B to find alpha_AD. Then use one last acceleration equation to find A_D.
ReplyDeleteAlso, finding the instant center of AB will save you a lot of time here. You will need omega_AB in those acceleration equations dhoss mentioned.
ReplyDeleteso is the acceleration of B zero? If not, how do we solve with only one equation?
ReplyDeleteThe acceleration of B is only in the X direction, but you don't need to find it. You use the acceleration equation between A and B to find alpha_AD. There will be no component of acc_B in the j direction, which allows you to find alpha_AD
ReplyDeleteI understand that Ab is only in i direction. But, I still am confused about how to get alpha_ad from the accel eq. of A B ... is alpha_ad = alpha_ab?
ReplyDeletePlease note that DAB is a single rigid body. The rigid body has only one angular velocity and one angular acceleration regardless of which two points that you use in the acceleration equations of the rigid body.
ReplyDelete