First slide
Standing waves

A stretched string of length 1m and mass 5 × 104 kg, fixed at both ends, is under a tension of 20 N. If it is plucked at points situated at 25 cm from one end, it would vibrate with a frequency :


Standing waves of produced in the string attached on both the ends, whose frequency is given by  n2lTμ

T=20Nand   μ=5×104frequency=n24×104=100 n

Now according to question the string is plucked at 25 cm
Thus antinode is present at 25 cm, thus λ4=25 cm 
 λ=100 cm
 n=2, hence frequency = 200Hz

Get Instant Solutions
When in doubt download our app. Now available Google Play Store- Doubts App
Download Now
Doubts App