Waves

A wire \(P Q\) has length \(4.8 \mathrm{~m}\) and mass \(0.06 \mathrm{~kg}\). Another wire QR has length \(2.56 \mathrm{~m}\) and mass \(0.2 \mathrm{~kg}\). Both wires have same radii and are joined as a single wire. This wire is under tension of \(80 \mathrm{~N}\). A wave pulse of amplitude \(3.5 \mathrm{~cm}\) is sent along the wire \(\mathrm{PQ}\) from end \(\mathrm{P}\). the time taken by the wave pulse to travel along the wire from point P to R is ?