A string fixed at both ends vibrates in three loops. The wave length is $10\, cm$ . The length of string is …. $cm$

A wave travelling along positive $x-$ axis is given by $y = A\sin (\omega \,t – kx)$. If it is reflected from rigid boundary such that $80\%$ amplitude is reflected, then equation of reflected wave is

When a wave travelling in medium is reflected from the boundary of a denser medium, which of the following will not change?

The fundamental frequency of vibration of a string stretched between two rigid support is $50\,Hz$. The mass of the string is $18\,g$ and its linear mass density is $20\,g / m$. The speed of the transverse waves so produced in the string is $……….\,ms ^{-1}$

A wire of density $9 \times 10^3 kg /m^3$ is stretched between two clamps $1 m$ apart and is subjected to an extension of $4.9 \times 10^{-4} m$. The lowest frequency of transverse vibration in the wire is ….. $Hz$ ($Y = 9 \times 10^{10} N / m^2$)