## Question

The length of a sonometer wire *AB* is 100 cm. Where should the two bridges be placed from end *A* to divide the wire in three segments whose fundamental frequencies are the ratio of 1:2:3?

### Solution

60 cm, 90 cm

For a wire, Therefore, frequencies will be in the ratio of 1:2:3 if lengths are in the ratio of the lengths are in the ratio of 6:3:1. Total length = 100 cm. Therefore *L*_{1} = 60 cm, *L*_{2} = 30 cm and *L*_{1} = 10 cm.

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