Question

A spherical wave with a wavelength of 4.0 m is emitted from the origin. at one instant of time, the phase at r = 8.0 m is πrad. at that instant, what is the phase at r = 7.5 m ?

Answer 1

phase of the wave at r = 7.5 m is given as

`\Delta \phi = (15)/(16)\pi`

Step-by-step explanation:

As we know the relation between phase difference and path difference is given by

`\Delta \phi = (2\pi)/(\lambda)\Delta x`

now we know that phase of wave is 180 degree at a distance r = 8 m

so here we have

`\pi = (2\pi)/(\lambda)(8m)`

`\lambda = 16 m`

now we have to find the phase at r = 7.5 m

so again by above formula

`\Delta \phi = (2\pi)/(16)(7.5)`

`\Delta \phi = (15)/(16)\pi`