Laser e gas lamp: o que têm em comum

1. Passo 1. Laser — é feito de — Semiconductor. Maiman’s first laser was a ruby crystal; today it is more often a semiconductor.
2. Passo 2. Semiconductor — é material para — Photoresistor. Selenium and cadmium sulfide are semiconductors.
3. Passo 3. Photoresistor — faz parte de — Street light. Switching on at dusk.
4. Passo 4. Street light — evoluiu de — Gas lamp. Gas lamps.

Abrir Evothings