Question

Give two uses of Infrared Rays.

Answer 1

Hint: Here we will discuss different uses of infrared rays. Although there are a whole lot of places where infrared radiations are used, here we will only be discussing the two of them namely, thermal imaging and infrared astronomy.

Complete step-by-step solution:
Infrared rays are used in a variety of fields ranging from everyday life to military uses and even used in astronomy. In everyday life, they are used in TV remotes. The Military uses them for thermal imaging and there is a complete branch of astronomy called infrared astronomy.
Infrared rays are emitted by all hot objects. The hotter the object more is the amount of infrared radiation emitted by it. This is used by police and the military to check for human presence and plan their actions accordingly. The human body has an average temperature of 37 degrees Celsius and this is higher compared to surroundings so on a camera capable of detecting thermal radiation, humans show up very easily. The same technique and principle were used recently to make thermometers that can detect the temperatures without contact and were very useful in stopping the spread of the coronavirus.
Infrared astronomy is a branch of astronomy where we use infrared radiation given by celestial objects to gather information about them and know more about the conditions there. It is used to know about the temperatures of stars which further helps in the calculation of the age, the lifetime of the star, and the composition of the star.

Note: Human eye cannot perceive infrared rays and therefore special equipment is required to detect them. One simple method you can use to see infrared rays is the camera of your mobile phone. Point your TV remote towards your camera and click any of the buttons you will see a red light flickering on the top. Nowadays, many manufacturers are using radio waves for TV remotes as they pass through the solid surface easily due to their larger wavelength and do not require for you to point the remote towards the device and also works if the device is blocked by some thin material.