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1. If V for a particular metal is 5000 m/sec and a part made of that material is 3 mm thick, what is the transit time for the pulse to cross the material and reflect back to the source/receptor?

2. With nondestructive inspection methods using wave phenomena, the detection limit or resolution depends on the wavelength being used. Compare the wavelengths of:

a. Ultrasonic waves of frequency 500,000 Hz

b. X-rays

c. Acoustic emission stress waves of frequency 1 MHz Note: Velocity = frequency x wavelength.