Solve the question of and select the option from the choices A through D/E. Check your Answer and view the explanation.
Question: 8
Consider the following statements about ultrasonic waves:
1. They can destroy insects
2. They can clean clothes by removing dust
3. They can be used to treat disease
4. They can control automatic doors
Of the above statements
- 1 and 2 are correct
- 3 and 4 are correct
- 1, 2 and 3 are correct
- All are correct
Show/Hide Explanation
Correct Answer: D
0
Sound waves are longitudinal-mechanical wave. Sound waves are divided into three categories that cover different frequency range; Audible wave (20 Htz- 20,000 Htz), Infrasonic waves (<20Htz) and Ultrasonic waves (>20,000 Htz). Ultrasonic waves are used to destroy insects, clean clothes by removing dust, treat diseases, control automatic doors, detection of aircraft and submarine, determination of depth of sea etc.