Answer the following in brief:
1. Explain the working of SONAR.
SONAR stands for . It is a technique that uses ultrasonic waves to .
A SONAR device sends . When these waves strike an underwater object, they are . The device measures the time taken . Using the speed of sound in water and the measured time, the distance of the object can be calculated.
2. A radar signal is reflected by an aeroplane and is received \(2\times 10^{-5}\ s\) after it was sent. If the speed of these waves is \(3\times 10^{8}\ m/s\), how far is the aeroplane from the radar?
The distance between aeroplane and radar is \(=\) \(m\)