Question 9: Can we apply Huygens principle to radar waves?
Radar is the abbreviation of Radio Audio Detection And Ranging. A radar system transmits Electromagnetic waves in the air. When the waves are scattered by a target, such as an aero plane in the air, it is received by the system again.With the time interval in the two way journey of the wave, the presence of the target (such as an aero plane or missile) is detected. Similarly, the received waves are displayed on a Cathode Ray Oscilloscope (CRO). If the amplitude of the received wave (as shown by the CRO) is increasing it will mean that the target is approaching and if it is decreasing, the target will be moving away from the system.
According to Huygens Principle, each point on the radar wave acts as a source of the secondary wavelets. So we can find the wavefront of the radar wave as it moves through a certain region.
Hence Huygen’s principle can be applied to RADAR waves.