The displacement of partcles in a string streched in the x-direction is by `y`. Among the following expressions for `y`, those describing wave motion are :

Options

A. (a)`cos kx sin omegat`
B. (b) `k^(2)x^(2) - omega^(2)t^(2)`
C. ( c ) `cos^(2) (kx +omegat)`
D. (d) `cos(k^(2)x^(2) - omega^(2)t^(2))`

Answer

A, C

Explanation

(a,c) For wave motion, the differential equation is `(del^(2)y)/(delt^(2)) = (constant (omega^(2))/(k^(2))) (del^(2)y)/(delx^(2)` …(i)