Q.

While measuring the speed of sound by performing a resonance column experiment, a student gets the first resonance condition at a column length of 18 cm during winter. Repeating the same experiment during summer, she measures the column length to be x cm for the second resonance. Then

1 18>x   
2 x>54   
3 54>x>36   
4 36>x>18   

Ans.

(2)

V=VRTM⇒V∝T,

f=V4l⇒l∝V,

l1=18cm⇒l2=54cm

l1'>18cm⇒l2'>54cm