Cutting Edge Materials: Practicals

Six groups of practicals produced by the Institute of Physics (IOP) that help students to find out more about how science is applied to using and testing new materials.

In addition to the guidance included for specific activities, please refer to the generic health and safety information before commencing any practical activity.

The resource is accompanied by the Teacher and technicians' guide for both the practicals and activity sheets.

[b]Work on a coil[/b]
This practical activity provides useful practice in using work done = force x distance and introduces students to memory metal in a dramatic way. It is suitable for mixed ability classes, with extension work on applications of memory metal.

[b]Muscle metal[/b]
An activity accessible to foundation tier students.They use a shape memory alloy called Nitinol (muscle metal) to explore energy transformation and mechanical work.The investigation which is the central part of the activity requires students to consider the reliability of their evidence before they can state a conclusion.The final experiment allows them to select one of two possible models of the agent responsible for the contraction of hot muscle metal.

[b]Muscle wire[/b]
An activity designed for higher tier students. As well as comparing the
behaviour of a smart material with its biological equivalent, it invites students to use their evaluation of experimental evidence to make judgments about the fitness of scientific theories. After following a procedure to measure the work done by a loop of Nitinol wire when heated by an electric current, students are required to:
• consider two alternative theories for the wire
• carry out experiments to test those theories
• decide which theory is best
• devise another experiment to test the best theory.

[b]Muscle wire efficiency[/b]
An activity aimed at higher tier students. It requires them to perform calculations with the following formulae:
• power = voltage x current
• energy = power x time
• work = force x distance
*effciency = useful energy output/energy input
They are introduced to Nitinol wire, a shape memory alloy which can transform electrical energy into mechanical work, albeit with an efficiency of less than 1%.The extension activity requires students to perform an extra experiment to test a theory about the low efficiency.

[b]Circuit training[/b]
This activity can be used to assess the construction, testing and evaluation of an electronic device. Students should work individually and may need extra guidance to achieve assessment requirements as set out in the relevant awarding board specifications.

[b]High temperatures[/b]
An ordinary household light bulb is adapted as a temperature probe for measuring high temperatures, demonstrating the increase in electrical resistance of a metal when heated. It has a thin metal filament, usually made out of tungsten, which has a very high melting point (3422 degrees C).