Two wires of same material and radii r and 2r respectively are welded together end to end. The combination is used as a sonometer wire and kept under tension T. the welded point is mid-way between the two bridges. When stationary waves are set up in the composite wire, the joint is a node. Then the ratio of the number of loops formed in the thinner to thicker wire is,(a) 2 : 3(b) 1 : 2(c) 2 : 1(d) 5 : 4
sumit kumar , 11 Years ago
Grade Upto college level
2 Answers
Arun
Last Activity: 4 Years ago
Let n1 and n2 be the no of loops formed in the wires of radii r and 2r respectively. f1=2ln1μ1T f2=2ln2μ2T where μ1 and μ2 are mass per unit lengths of the wires.
Since the welded wire is continuous, f1=f2 ∴n2n1=μ2μ1=π(2r)2πr2=41=