Propagation of Sound Waves — Question 1

(a) Given,

Heart beats 75 times a minute

Converting minute into seconds, we get,

1 min = 60 s

As, frequency (f) is the number of times the heart beats in a second

Therefore, we get,

$\text f = \dfrac{75}{60} \\[0.5em] \text f = 1.25 \text{ s}^{-1}$

Hence, Frequency = 1.25 s^-1

(b) Time period t = $\dfrac{1}{\text f}$

Substituting the values, we get,

$\text t = \dfrac{1}{1.25} \\[0.5em] \text t = 0.8\ s$

Hence, t = 0.8 s