Vitek VTC-3516 Spécifications télécharger pdf (Page 60)

Design and Applied Technology (Secondary 4-6)

Electro-rheostatic (ER) materials will turn from a thick fluid (high viscosity; similar to motor

oil) into an almost-solid substance within as soon (in milliseconds) as exposed to an electric

field. The fluid state will be resumed almost as soon as the field is removed. ER fluids may

simply be made of milk chocolate or cornstarch plus oil. They can be used in clutches and

valves, and engine mounts for reduction of noise and vibration in vehicles.

Magneto-rheostatic (MR) materials change and reverse likewise when exposed to a magnetic

field. MR fluid could be made of small iron particles suspended in oil. They can be used for

damping the vibrations of exercise equipment, prosthetic limbs, vehicle shocks, washing

machines, etc.

A shape memory alloy (SMA) changes its shape when heated to a designated temperature.

SMA can be used in medical / surgical parts, devices in control systems, etc. For example, an

SMA pin which is out of shape can resume to its original shape when immersed in a cup of

hot water. Nickel titanium (NiTi) is an SMA.

S T O P A N D T H I N K

New technologies give human beings double-edged quality of life: more comfortable,

convenient, etc, but worse living environment if not being deployed properly.

Describe what designers and engineers should consider when building a mega dam for hydro

power generation.

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Vitek VTC-3516 Spécifications Page 60