Mechanical Concepts free demo
In CAST, CAST-R, POSS and MASS · about 3 minutes · Choose an answer (two or three options per picture)
About the Mechanical Concepts section
Mechanical Concepts is the section to practice first, because it is the one section shared by every battery we cover. EEI's CAST, CAST-R, POSS and MASS brochures all describe 44 questions in 20 minutes, and the TECH brochure describes the same section again. Work on it once and it counts whichever job you are applying for.
The questions are pictures rather than words: a pair of meshed gears, a belt drive, a lever with a load on it, a pulley system, water in connected vessels, a body on a slope. You are asked which way something turns, which arrangement needs less effort, where pressure is greatest, which setup is more stable. Nothing needs to be calculated.
At under 30 seconds a question there is no time to reason from first principles on every item, so the aim of practice is to make the common arrangements instantly recognizable. Our items are drawn by generator, so the arrangements vary every run, and every explanation names the principle involved rather than just the answer.
Tips from practice
- Learn the handful of recurring principles — meshed gears reverse, a bigger gear turns slower, more supporting ropes means less effort, the longer lever arm wins.
- Trace the motion with your finger from the driver to the part in question; it stops direction errors.
- Answer and move on. At 44 questions in 20 minutes, two slow items cost you three easy ones.
- If you truly do not know, choose and move on — EEI's brochures state there is no penalty for guessing, so a blank is strictly worse.
Common questions
- Is this section the same in CAST, POSS and MASS?
- EEI's brochures for CAST, CAST-R, POSS and MASS all describe the section the same way, with the same count and time limit, so practice carries across. We cannot see the actual item pools, so treat that as the published description rather than a guarantee that the questions are identical.
- Do I need to learn formulas?
- No. The section is about understanding how mechanisms behave, not about calculating. Mathematical Usage is the section that involves formulas.
This demo is independent practice, written from publicly published descriptions of the section. It is not affiliated with or endorsed by the Edison Electric Institute or any utility, and it is not identical to any real test.