Question

The equations of two sound waves are given by $Y_{1}=3 \sin 100\, \pi t$ and $Y_{2}=4 \text{Sin} 150\, \pi t$. The ratio of the intensities of sound produced in the medium is

• A. $1: 2$
• B. $1: 4$
• C. $3: 4$
• D. $4: 3$

Answer 1

Answer: (B)

$A _{1}=3, f _{1}=100 \pi / 2 \pi=50\, Hz$
$\,\&\, A _{2}=4, f _{2}=150 \pi / 2 \pi=75\, Hz$
$\frac{I_{1}}{I_{2}}=\frac{(3 X 50)^{2}}{(4 X 75)^{2}}=\frac{1}{4}$