Question

Two wires of same material and area of cross sec-
tion, having lengths 30 cm and 40 cm are stretched
between two ends with tensions 10 N and 20 N,
respectively. The difference between the funda-
mental frequencies of two wires is 4.0 Hz. Find the
linear mass density of the wire.​

Answer 1

Here in this case ,for a stretched string ,

n=12lTm−−√Now , we know from the question ,n2−n1= HzSo , n1=12×0⋅310m−−√ and n2=12×0⋅420m−−√So ,12×0⋅420m−−√−12×0⋅310m−−√=4Now solving you will get that , m=6⋅4×10−3 kg/m .