Question

Infrared radiation has frequencies from 3.0×1011 to 3.0×1014 Hz, whereas the frequency region for visible light is 4.3×1014 to 7.5×1014 Hz.

We can say that:

1. The speed of infrared radiation is ____ (higher than, lower than, the same as) visible light.

2. The wavelength of infrared radiation is ____ (higher than, lower than, the same as) visible light.

Answer 1

Answer :-

1. The speed of Infrared radiation is The same as visible light.

Electromagnetic spectrum consist of different radiations like gamma rays, X rays, Ultra violet, visible, Infrared, microwave, radio waves. The only difference between these radiation is of their wavelength or frequency. All these electromagnetic radiations travels at the speed of light in vaccum. So Infrared radiation and Visible radiation travels at the same speed. However, if the frequency increases the wavelength decreases but it does not affect the speed of radiation.

2. The wavelength of Infrared radiation is Higher than visible radiation. In electromagnetic spectrum Infrared radiation exist in between microwave radiations and visible radiations. Microwave radiations are higher in wavelength than Infrared radiations and visible radiations are lower in wavelength than Infrared radiation.

Wavelength of IR radiation is 700 nm to 1mm and wavelength of visible radiation is 400 nm to 700 nm. From this we can conclude that Infrared radiations are higher in wavelength than visible radiations.