Practice portal › Waves › Standing Waves in Strings

A sonometer wire 114 cm long is fixed at both ends. Where should the two bridges be placed to divide the wire into three segments whose fundamental frequencies are in the ratio 1:3:4?

Asked in JEE Main Online 2013 · Sonometer

Answer: (4) At 72 cm and 96 cm from one end

Step-by-step solution

For a fixed tension and wire, f∝1/L, so the lengths are in the ratio 1:1/3:1/4=12:4:3.

The total is 19 parts over 114 cm, so one part is 6 cm and the segments are 72 cm, 24 cm and 18 cm.

The bridges therefore sit 72 cm and 72+24=96 cm from that end.

Why the other options are wrong

More Standing Waves in Strings questionsAll Standing Waves in Strings questions →

Reading this solution needs no sign-in. You only sign in to practise against the clock and keep your progress.

Practise this with a timer