A hospital uses an ultrasonic scanner to locate tumours in a tissure. What is the wavelength of sound in the tissure in which the speed of sound is `1.7 km s ^(-1)` ? The operating frequency of the scanner is `4.2 ` MHz.

Explanation

Velocity of sound in a given medium is `v = g lamda `
`therefore lamda = (v)/(f) = (1.7 xx 10 ^(3))/(4.2 xx 10 ^(6)) = 4.047 xx 10 ^(-4) m`