Physics

Problem

The fundamental frequency of a sonometer wire is

180\,\text{Hz}

when its vibrating length is

80\,\text{cm}

, the tension remaining unchanged. With this setting a tuning fork produces

12

beats per second. The vibrating length of the wire is now reduced to

75\,\text{cm}

without altering the tension and no beats are heard. The frequency of the tuning fork is a)

204\,\text{Hz}

192\,\text{Hz}

168\,\text{Hz}

180\,\text{Hz}