Waves - Result Question 47

49. The length of the wire between two ends of a sonometer is 100cm. What should be the positions of two bridges below the wire so that the three segments of the wire have their fundamental frequencies in the ratio of 1:3:5 ?

[NEET Kar. 2013] (a) 150023cm,200023cm

(b) 150023cm,50023cm

(c) 150023cm,30023cm

(d) 30023cm,150023cm

Show Answer

Answer:

Correct Answer: 49. (a)

Solution:

  1. (a) From formula, f=1xTm

f1l

l1:l2:l3=1f1:1f2:1f3

=f2f3:f1f3:f1f2

=15:5:3

[Given: f1:f2:f3=1:3:5 ]

Therefore the positions of two bridges below the wire are

15×10015+5+3cm and 15×100+5×10015+5+3cm

i.e., 150023cm,200023cm



NCERT Chapter Video Solution

Dual Pane