Ways of knowing in designing and making

It is one thing to know that voltage = current x resistance (Ohm's Law) and all that follows from that law; it is quite another matter to know how to arrange and connect a number of light bulbs to a battery to get the right lighting effect in a model theatre.

It is one thing to know that cables supplying current to a load become warm; it is quite another matter to know how to avoid overheating (and melting) an extension cable, on a drum, when using it to run an electric heater.

Conersely, it is easier to get the right mix of sand, cement and water for bricklaying by experience through trial and error than it is to read about it in a book.

You may know how to ride a bicycle, do a wheelie, or control a skateboard, but do you need to know the dynamic theory before you start?

Much of what is done in design and technology depends on know-how rather than knowing the theory behind it. However, once the know how is there, it becomes easier to understand the theory behind it and move on to more complex activities in the same field. (The 'wheelie cyclist' moves on to being able to bump the cycle up steps or, even, to riding a mono-cycle!).

Transferring know-how

An important feature of design and technology is that many of the know hows are similar in different fields. For instance, the resonance of the rocking horse is the same resonance as in:

• a pendulum clock
• a skipping rope
• a string on a violin
• the column of air in an organ pipe
• a swing in a playground
• a howl in a loudspeaker system
• a car suspension system
• an electronic circuit
• a quartz crystal controlling a watch or clock
• standing waves generating a laser beam
• the magnetic resonance of water molecules which show up on an MRI scan of the human body.

See Ideas: strategies for thinking for some suggested strategies for developing ideas by transferring your understanding from familiar to unfamiliar situations. Technology transfer is a similar, very useful strategy.