# O: Engineering Engineering is an applied science, which uses an understanding of systems to design tools and engines that can assist mankind.

The IB Physics course contains two key sections at Standard Level:

• Rigid bodies and rotational dynamics (4 pages) - using the rotational equivalents to translational physical quantities to perform calculations for sprinng or rolling bodies
• Thermodynamics (4 pages) - defining the first and second laws of thermodynamics, representing gas changes on diagrams, and designing engines with net work done

At Advanced Higher Level, you will study fluids and fluid dynamics and damped and driven oscillations.

• ### Torque and moment of inertia

Torque, also known as the moment of a force, is defined as the product of a force and the perpendicular distance from the line of action to the pivot.

• ### Equilibrium and angular acceleration

A body is in rotational equilibrium if the sum of the anticlockwise torques is equal to the sum of the clockwise torques about a pivot.

• ### Rotational dynamics

An object experiences angular acceleration if it is not in rotational equilibrium. The equations for linear motion have rotational equivalents.

• ### Angular momentum and rotational kinetic energy

The rotational equivalent of linear momentum is angular momentum. It is defined as the product of moment of inertia and angular velocity. We can also calculate rotational kinetic energy.

• ### First law

Thermodynamics is the study of the movement of heat and its relationship with work.

• ### Processes

We can use diagrams to show the processes that take place in a container of gas. A graph of pressure vs volume enables us to show all possible types of process.

• ### Second law

A heat engine converts thermal energy into mechanical work. The second law of thermodynamics can be expressed in three ways.

• ### Cyclic processes

A cyclic process is a series of transformations that take the gas back to its original state. These form a closed loop on a pV diagram.

• ### AHL Static fluids

Don't be fooled into thinking that only solids are 'heavy' and that we can approximate everything as a volume-less particle. Fluids, such as liquids, have a density, exert an upward buoyancy on anything that should displace them, have increasing pressure w

• ### AHL Fluid dynamics

Fluid dynamics is the study of moving fluids. As with moving bodies, mass and energy are conserved leading to equations that can be used to determine unknown quantities. An understanding of fluid properties enables us to calculate drag forces and the categ

• ### AHL Damped and driven oscillations

In the simple harmonic motion topic we considered natural oscillations of pendula and masses on springs. But so far we have ignored the effect of the fluid in which the oscillations are taking place and therefore the effects of damping. And what if these o