Mechanics

Mechanics is the part of physics concerned with why and how things move — forces, motion, and energy — and it's usually the first major unit in any physics course because most of what comes later, like electricity, waves, and thermodynamics, reuses the same underlying framework of forces and energy conservation. The subject splits fairly cleanly into two related strands: kinematics, which describes motion mathematically — position, velocity, acceleration, and how they relate over time — without worrying about what caused it, and dynamics, which brings in Newton's three laws to explain why an object moves the way it does.

A lot of early confusion comes from mixing the two up, trying to explain a kinematics graph using force reasoning or vice versa, when they're genuinely separate tools that get combined later. Newton's second law, F = ma, looks simple written down but causes real trouble in practice, mostly because most real problems involve multiple forces acting at once — gravity, friction, normal force, tension — and the actual skill is drawing an accurate free-body diagram before any equation gets written; students who skip that step tend to plug numbers into the wrong places.

Energy methods, using work and kinetic and potential energy, offer an alternative route through many of the same problems and are often faster once a student trusts them, though getting there requires believing that a scalar quantity like energy can fully substitute for the vector reasoning of forces in the right circumstances.

Rotational motion — torque, angular momentum, moment of inertia — extends the same ideas to spinning objects and tends to show up later, once linear mechanics is solid. A tutor can focus specifically on free-body diagrams, on choosing between force and energy methods for a given problem, or on whichever of these strands is the actual gap.