Ultrasound. High-frequency sound waves (ultrasound) are used to probe the interior of the body, much as x rays do. To detect a small objects such as tumors, a frequency of around 5.10 MHz is used. What are the period and angular frequency of the molecular vibrations caused by this pulse of sound

Explanation:

Frequency of sound   n  = 5.1 MHz = 5.1 x 10⁶ Hz

angular frequency ω = 2π x n

= 2 x 3.14 x 5.1 x 10⁶ rad /s

= 32.028 x  10⁶ rad /s

period of vibration = 1 / n

1 / 5.1 x 10⁶

= .196 x 10⁻⁶ s

T  = .196 μs

a.metals can become magnetic if they have many spinning electrons that create magnetic fields.d.only some metals are attracted by magnets; these metals are called ferromagnetic.

d.wrapping an insulated wire around a metal with ferromagnetic properties and applying an electric current.

it is a negative acceleration