Infrared Technology and Wireless Communication

The video tutorial explores the evolution of the term 'wireless', initially used to describe radio technology during World War I. It then delves into various wireless technologies, focusing on infrared technology. Infrared, though not common in modern mobile devices, is still used in remote controls. The tutorial explains the properties of infrared, such as its requirement for line of sight and its low energy, which limits its range to less than 10 meters.

What was the original meaning of 'wireless' during the First World War?

• A form of telegraph

• A type of computer

• A radio transmission device

• A type of mobile phone

How has the concept of 'wireless' changed over time?

• It is no longer used in modern language.

• It encompasses various technologies that connect without wires.

• It is only used for radio technology.

• It now refers to any technology that uses wires.

Which of the following is a characteristic of infrared technology?

• It is commonly used in mobile phones.

• It requires a direct line of sight.

• It can transmit signals over long distances.

• It is visible to the human eye.

Why is infrared not commonly used in modern mobile phones?

• It is not secure enough for data transmission.

• It is too expensive to implement.

• It requires too much power.

• It has a limited range and requires line of sight.

In the electromagnetic spectrum, where is infrared located?

• Between gamma rays and X-rays

• Below visible light

• Above visible light

• Between ultraviolet and visible light

What is the theoretical distance limit for infrared communication?

• Less than 1 meter

• Less than 10 meters

• Less than 100 meters

• Less than 1000 meters

Why are Blu-ray players named as such?

• They are manufactured by a company named Blu.

• They use a red laser.

• They use a blue laser with higher energy.

• They were developed in the 1990s.

What is a common use of infrared technology today?

• In satellite communications

• In mobile phone communication

• In remote controls for TVs and air conditioners

• In high-speed internet connections

What is a limitation of infrared signals?

• They do not last very long.

• They can be easily intercepted.

• They are affected by magnetic fields.

• They require a lot of energy.

Which of the following devices commonly uses infrared technology?

• Wireless routers

• Smartphones

• Laptops

• Television remote controls