Watch our video!
All motion, both 2D and 3D, are a combination of “pure translation” plus “pure rotation”. And the order does not matter. Since there are so few 3D problems that can be solved without a computer, 2D problems are the most likely to be seen on the PE Exam.
Examples that you might see on the PE Exam are mostly limited to 3 or less members. A common single member problem would be the rolling wheel, a common two member problem would be a simple hoist, and a common three member problem would be a slider-crank mechanism. All three of these are explained in detail in other presentations. However, the key to their solution is breaking the motion down into a combination of rotation and translation, though some members have only translation and other members have only rotation.
For example, the block in a simple hoist moves only vertically and the pulley only rotates. For a rolling wheel, rotation and translation are present. And for a slider-craink mechanism, the crank is in pure rotation, the slider is in pure translation, and the connecting rod has both rotation and translation.
Again, the key to solving problems is recognizing the motion of each member and applying the equations of motion and the kinematics appropriately. – Dr. Tom
Mechanical PE Exam Prep That Works
Pay Up Front and Save $100!
Test Drive Your Course for Only $50!
Pay-As-You-Go and Start for Only $50!
Don’t miss out on the latest posts (and more)! Follow DTC on:
