The infronic sound is used successfully in drilling deepest wells because the ___ vibrations break up hard rock more easily than the ordinary drill do.
A. Low frequency
B. Medium frequency
C. Unequal frequency
D. High frequency
Answer:D
The infronic sound is used successfully in drilling deepest wells because the ___ vibrations break up hard rock more easily than the ordinary drill do.
A. Low frequency B. Medium frequency C. Unequal frequency D. High frequency