The instantaneous velocity and acceleration of slider B are

The instantaneous velocity and acceleration of slider B are shown in the figure. 8. Determine the corresponding angular acceleration of bar AB. (1) 18 rad/sec^2 CCW (2) 4.62 rad/sec^2 CCW (3) 12 rad/sec^2 CCW (4) 6.93 rad/sec^2 CCW (5) 6.93 rad/sec^2 CW (6) 12 rad/sec^2 CW (7) 18 rad/sec^2 CW (8) None of the above 9. Determine the corresponding angular acceleration of bar OA. (1) 5.26 rad/sec^2 CW (2) 12.06 rad/sec^2CW (3) 0.643 rad/sec^2 CCW (4) 8.59 rad/sec^2 CW (5) 8.59 rad/sec^2 CCW (6) 12.06 rad/sec^2 CCW (7) 5.26 rad/sec^2 CCW (8) None of the above

Solution

Angular acceleration x radius is linear accelaration. In question 8 we do not have the dimension of link AB. So it will not be possible to draw the space diagram, hence let us work with the answer options. The angle at point A is 30 degrees. So in terms of radians this will be 0.523 radian. Now multiply this with all the answer choices. Divide the linear accelration 10 inches per seccond by these vlues. You get the radius of the link AB for each option. Now with this draw your space diagram and check the closest answer to point B. Answer option 4.62 rad/sec2 will be the approximate value. With the same diagram the answer for question 2 can be found out as 5.26 rad/sec2.