The working principle of radar is to multiply the time difference between transmitting pulse and receiving pulse by the propagation speed and light speed of electromagnetic wave, so as to get the accurate distance between radar and target.

A device that uses extremely short radio waves for detection. Radio waves will be reflected when they encounter obstacles during propagation. According to this principle, the radar sends out radio waves, and then uses the receiving device to receive the reflected radio waves, so as to determine the direction, distance and size of the target, and then reflects the received radio waves to the indicator to obtain the image of the detected target.

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Bat and Radar is the text of Lesson 26, Unit 6, Book 2, Grade 3, Shanghai Education Press. This article mainly tells that scientists have revealed the reasons why bats fly at night through repeated experiments, and inspired them to install radar on the plane, thus solving the problem of flight safety at night.

Scientists got a hint from bats to install radar on the plane to ensure their safe flight. This study shows that studying biology may have an impact on human creativity.