For the travelling harmonic wave
`y(x,t) = 2.0 cos 2 pi (10 t - 0.0080 x + 0.35)`
where x and y in cm and t in s. Calculate the phase difference between oscillatory motion of two points seperated by a distance of
(a) 4 m,
(b) 0.5 m,
(c ) `lamda//2`,
(d) `3lamda//4`

Explanation

(a) `6.4 pi` rad (b) `0.8pi` rad (c ) `pi` rad (d) `(pi//2)` rad