The working of a transducer can be understood by the mic of telephones that we use in our daily life. The mic converts sound into electrical signals and amplify it to the required range. Then this electrical signal is transmitted at the output which gets transformed from the electrical signal into sound by a transducer.
Another example to understand the working of transducers is when it is used in a fish-finder. It is used in the echo sounder system. It converts electrical pulses into sound. In other words, it sends out sound waves and gets back the echo that is interpreted by the echo sounder. The transducer receives transmit pulse that are high voltage electrical pulses from the echo sounder. Then it converts the transmitted pulses into sound. The sound travels through the water as a pressure wave and when it strikes an object like a rock or a fish, the wave bounces back.
When this wave bounces back, the transducer acts as a microphone and converts it into electrical energy. The echo sounder calculates the time difference between the transmitted pulse and the echo returning from the objects, then this information is displayed on the screen that can be easily understood by the user.