Two pulses travel in mutually opposite directions in a string with a speed of $2.5 \ cm/s$ as shown in the figure. Initially,the pulses are $10 \ cm$ apart. What will be the state of the string after two seconds?

Two waves are superimposed whose ratio of intensities is $9: 1$. The ratio of maximum and minimum intensity is

Two waves of amplitudes $A_1$ and $A_2$ respectively are superimposed. The ratio between the maximum and minimum intensities of the resultant waves is $9 : 4$. The value of $A_2 / A_1$ is [Assume $A_1 > A_2$]

Two waves each of intensity $I$ interfere with a phase difference of $120^o$. The resultant intensity of the waves will be:

$A$ person standing at a distance of $6\, m$ from a source of sound receives sound waves in two ways: one directly from the source and the other after reflection from a rigid boundary,as shown in the figure. The maximum wavelength for which the person will receive maximum sound intensity is .... $m$.

The superposition takes place between two waves of frequency $f$ and amplitude $a$. The total intensity is directly proportional to