Question

In a resonance column experiment , the first resonance is obtained when the level of the water in the tube is at `20 cm` from the open end . Resonance will also be obtained when the water level is at a distance of
A. `40 cm` from the open end
B. `60 cm` from the open end
C. `80 cm` from the open end
D. `100 cm` from the open end

Answer 1

Correct Answer - B
For second resonance
`L_(2) = ( 3lambda)/(4) = 3L_(1) = 3 xx 20 = 60 cm`