1478 
4 
Region (a) 
Density p, 
Sound Velocity C, 
yo plane 
Region (2) 
Density paz 
Saund Velocity Ce ren 
1 alfecee a 
Oblique reflection of a plane wave at a plane interface. 
@,- angle of incidence and reflection. 
®,s angle of refraction 
P:» Pe» P, incident, reflected and refracted wave 
trains respectively. 
