Mechanics
Classical mechanics is the set of physical laws describing the motion of bodies under the influence of a system of forces. Take a look at the Cavendish balance or the Kater Pendulum.
Thermodynamics
Thermodynamics is a branch of science concerned with heat and temperature and their relation to energy and work. The behavior of these quantities is governed by the four laws of thermodynamics, irrespective of the composition or specific properties of the material or system in question.
Electricity & Magnetism
Electromagnetism studies the behavior of charged particles and electric and magnetic fields.