AS/A2 Mech 2 Mech 3

M1 Topic 1: Mathematical models
Basic concepts
Much of mechanics is concerned with modelling forces.

Please enable Java for an interactive construction (with Cinderella).

A correctly labelled diagram is an essential part of studying a mechanics problem and you should always draw one first before doing anything else. If the diagram is correct it can often make a mechanics problem very easy to answer. The above diagram shows an object on a slope. You can alter the position of the object (yellow point) and the angle of the slope (black points). The object is modelled as a particle. The blue lines, or vectors, show the forces representing gravity (mg) and normal reaction (R) that act on that particle. The two red vectors represent a resistant force (often friction) and a driving force. Which is which dependeds on the direction of slope. Some situations may also involve tension and thrust, air resistance or upthrust.

Summary Cinderella interactive geometry.