The ultrasonic transducer used in a medical ultrasound imaging device is a very thin disk (m = 0.10 g) driven back and forth in SHM at 1.0 MHz by an electromagnetic coil. Part A) The maximum restoring force that can be applied to the disk without breaking it is 30,000 N. What is the maximum oscillation amplitude that won't rupture the disk? Part B) What is the disk's maximum speed at this amplitude?

Respuesta :

Explanation:

It is given that,

Mass of the disk, [tex]m = 0.1\ g = 10^{-4}\ kg[/tex]

Frequency of SHM, [tex]f=1\ MHz=10^6\ Hz[/tex]

(A) Maximum restoring force, F = 30,000 N

We need to find the maximum oscillation in the amplitude that won't rupture the disk. We need that maximum acceleration of the particle in SHM is :

[tex]a_{max}=A\omega^2[/tex]

A is the amplitude of oscillation

[tex]\omega=2\pi f[/tex] is the angular frequency

Also, F = ma

So, [tex]F=mA\omega^2[/tex]

[tex]A=\dfrac{F}{4\pi^2mf^2}[/tex]

[tex]A=\dfrac{30000}{4\pi^2\times 10^{-4}\times (10^6)^2}[/tex]

[tex]A=7.59\times 10^{-6}\ m[/tex]

(B) The maximum speed in SHM is given by :

[tex]v=A\times \omega[/tex]

[tex]v=7.59\times 10^{-6}\times 2\pi \times 10^6[/tex]

v = 47.68 m/s

Hence, this is the required solution.