A firecracker exploding on the surface of a lake is herd as two sounds on a boat close to the water surface. Sound A composite wire is made by joining two uniform wires. If l1 =l2=l and u1 =u2/9 =u. Tension in the string is T, u is mass per unit length. The lowest frequency such that the Junction is an antinode with a speed u in water and a speed in air is v. The distance from exploding firecracker to the boat isA uvt/u+vB t(u+v)/uvC t(u-v)/uvD uvt/u-v
Nancy Thakur , 8 Years ago
Grade 11
