A car blowing a horn of frequency $350\, Hz$ is moving normally towards a wall with a  speed of $5 \,m/s$. The beat frequency heard by a person standing between the car and  the wall is ..... $Hz$ (speed of sound in air $= 350\, m/s$)

A uniform rope of length $L$ and mass $m_1$ hangs vertically from a rigid support. A block of mass $m_2$ is attached to the free end of the rope. A transverse pulse of wavelength $\lambda _1$ is produced at the lower end of the rope. The wavelength of the pulse when it reaches the top of the rope is $\lambda _2$ . The ratio $\lambda _2/\lambda _1$ is

A tuning of fork of frequency $392\, Hz$, resonates with $50\, cm$ length of a string under tension $(T)$. If length of the string is decreased by $2\%$, keeping the tension constant, the number of beats heard when the string and the tuning fork made to vibrate simultaneously is

The wave described by $y = 0.25\,\sin \,\left( {10\pi x - 2\pi t} \right)$ , where $x$ and $y$ are in $meters$ and $t$ in $seconds$ , is a wave travelling along is

Fundamental frequency of sonometer wire is $n$. If the length, tension and diameter of wire are tripled, the new fundamental frequency is

The transverse displacement of a string (clamped at its both ends) is given by $y(x,t) = 0.06$ $sin\, (2\pi x /3)\, cos\, (120\, \pi t)$. All the points on the string between two consecutive nodes vibrate with