Two sources of waves are called coherent if [NCERT 1984; MNR 1995; RPMT 1996, 97; CPMT 1997; UPSEAT 1995, 2000; Orissa JEE 2002; RPET 2003; MP PMT 1996, 2004]

Both produce waves having the same velocity

Both have the same amplitude of vibrations

Both produce waves of the same wavelength

Both produce waves of the same wavelength having constant phase difference

Both produce waves having the same velocity

Two sources of waves are called coherent if [NCERT 1984; MNR 1995; RPM

1.	Two sources of waves are called coherent if [NCERT 1984; MNR 1995; RPMT 1996, 97; CPMT 1997; UPSEAT 1995, 2000; Orissa JEE 2002; RPET 2003; MP PMT 1996, 2004]
A.	Both have the same amplitude of vibrations
B.	Both produce waves of the same wavelength
C.	Both produce waves of the same wavelength having constant phase difference
D.	Both produce waves having the same velocity
Answer» D. Both produce waves having the same velocity