Mention two properties of infrared radiations which are similar to the visible light and two which differ from visible light.

Two properties of infrared radiations which are similar to the visible light are as follows:

1. Infrared radiations travel in a straight line like visible light, with a speed of 3 x 10⁸ m s^-1 in air or vacuum.
2. They obey the laws of reflection and refraction like visible light.

Two properties of infrared radiations which differ from the visible light are as follows:

1. Infrared radiations have wavelength in the range of 8000 Å to 10⁷ Å whereas wavelength of visible light is the range of 4000 Å to 8000 Å.
2. Infrared radiations do not affect ordinary photographic plate whereas visible light affects photographic plate.