Secondary Catalogue

This programme is about seawater. It is the most important liquid on Earth, not only from its sheer volume, but also because it has remarkable qualities. A few of them, like buoyancy, are common to all liquids - but seawater is also the cradle of life. Three key factors of water underpin life in the sea: water’s dissolving power, its tendency to keep a stable temperature, and its transparency to light. This programme explains the mechanisms and the outcomes of these key facts—and other things—that make seawater both weird and wonderful. Show Less

A body is said to be in a state of rest if its position does not change with respect to a reference point with the passage of time, and a body is said to be in a state of motion if its position changes with respect to a reference point with the passage of time. Show Less

In an inclined plane, the mechanical advantage is the length of the slope divided by the height of the inclined plane. The mechanical advantage of a wedge is determined by dividing the length of the wedge by its width. The mechanical advantage of a screw is the ratio of the circumference of the screw to the distance the screw advances during each revolution. Show Less

A lever is a rigid bar that is free to rotate or pivot on a fixed point called a fulcrum. In the case of a lever, we increase the input distance. The ideal mechanical advantage is calculated by dividing the distance from the fulcrum to the input force by the distance from the fulcrum to the output force. Show Less

The convex mirror is used in rear-view mirrors in vehicles because it forms an erect and smaller image of the scene behind the vehicles. Convex mirrors are used in street lights and in shops, big supermarkets, and other places as anti - theft devices.They are also useful in parking vehicles and in removing blind spots. Show Less

Nuclear energy generates massive amounts of electricity but also produces highly dangerous radioactive waste. This clip explains waste production in reactors, its treatment and containment and how technology continues to improve safety around nuclear fission. It also explores reprocessing of waste and summarises the costs and benefits of nuclear power generation. Show Less