Experience the Quality With Free Mechanical Aptitude Exam Questions That Helps Candidates Pass

A transformer uses electromagnetic induction to step up or step down AC voltages. It does not work with DC because induction requires changing current. Transformers are critical in power transmission and are frequently tested in aptitude exams.

Heating the air inside a balloon lowers its density compared to the cooler air outside. According to Archimedes’ principle, the balloon experiences an upward buoyant force equal to the weight of displaced air. Since the balloon plus heated air weighs less than the displaced air, it rises. This demonstrates how thermal expansion and density changes influence pressure and buoyancy.

Ohm’s Law (I = V ÷ R) shows that halving resistance doubles current. This principle is vital for understanding how electrical loads affect circuits and preventing overheating or overloads in machinery.

In a nutcracker, the fulcrum is at one end, the load (nut) is in the middle, and the effort is applied at the handles. This makes it a second-class lever, where the load is between the fulcrum and effort, giving mechanical advantage for cracking nuts.

On each face of the cube, the edge cubes (excluding corners) have exactly one painted face. Each face has 4 such cubes, and with 6 faces: 6 × 4 = 24. But corner cubes are double-counted, leaving 18. Visualization like this is key in mechanical reasoning.