Blue LEDs - Filling the World with New Light

Quiz Question

1.The white LED lamps are energy-efficient, long-lasting and emit a bright white light. Moreover, and unlike florescent lamps, they do not contain ____________.
Mercury
Calcium
2. Only the triad of _________, __________ and __________can produce the white light that illuminates the world for us.
Red, Blue and Green
Pink, Violet and Indigo
3.In the LED, electricity is directly converted into light particles, photons, leading to efficiency gains compared to other light sources where most of the electricity is converted to heat and only a __________ amount into light.
Small
Large
4.In the LED, electricity is directly converted into light particles, photons, leading to efficiency gains compared to other light sources where most of the electricity is converted to heat and only a small amount into light.
True
False
5.Incandescent bulbs tend to last _______ hours, as heat destroys the filament, while florescent lamps usually last around _______ hours. LEDs can last for _______ hours, thus greatly reducing materials consumption. (Refer to page-2)
1,000; 10,000; 100, 000
10,000; 100; 10
6. Blue LEDs - Filling the World with New Light
According to the above picture, what century was light bulb invented? (Refer to page-4)
21st century
19th century
7. During the 1990s, both research groups succeeded in further improving their blue LEDs, making them more efficient. They created different gallium nitride alloys using aluminum or indium, and the LED’s structure became increasingly complex.
True
False
8.Isamu Akasaki, Hiroshi Amano and Shuji Nakamura are rewarded for inventing a new energy efficient and environment friendly light source – the blue light-emitting diode (LED). In the spirit of _________, the Prize awards an invention of greatest benefit to mankind; by using blue LEDs.
Alfred Nobel
Charles Nobel
9.The red light-emitting diode was invented in the end of the 2000s.
True
False
10.

The LED lamp also holds great promise when it comes to the possibility of increasing the quality of life for the more than 1.5 billion people who currently lack access to electricity grids, as the low power requirements imply that the lamp can be powered by cheap local solar power.

True
False