Engine 2014: Electricity

1. A The acoustical energy is produced as a continuous wave and transmitted from one transducer and the reflected acoustical energy is received by a second transducer.
2. B The acoustical energy is produced as a continuous wave and transmitted from the transducer and the reflected acoustical energy is received by the same transducer.
3. C The acoustical energy is produced as rapid, short high intensity pulses and transmitted from one transducer and the reflected acoustical energy is received by a second transducer.
4. D The acoustical energy is produced as rapid, short high intensity pulses and transmitted from the transducer and the reflected acoustical energy is received by the same transducer.

Tip: press A-D to answer