Ultrasonics & Relativity Questions And Answers.

1.Which of the following effects can be used to produce ultrasonic waves?
A. Magnetostriction effect
B. Doppler Effect
C. Magnetic effect
D. Sound effect

2.When is ultrasonic waves produced using piezo electric oscillator?
A. At constant temperature
B. At resonance
C. At constant pressure
D. At constant voltage

3.Which of the following causes acoustical grating?
A. Magnetic waves
B. Electric waves
C. Magnetostriction effect
D. Ultrasonic waves

4.What is the principle for measurement of the velocity of ultrasonic waves?
A. Magnetostriction effect
B. Acoustical grating
C. Doppler Effect
D. Acceleration effect

5.What is cold welding?
A. Welding at very low temperature
B. Welding using ultrasonic waves
C. Welding under water
D. Welding at constant temperature