A shell is fired from a cannon with velocity v m/sec at an angle \[\theta \] with the horizontal direction. At the highest point in its path it explodes into two pieces of equal mass. One of the pieces retraces its path to the cannon and the speed in m/sec of the other piece immediately after the explosion is [IIT 1984; RPET 1999, 2001; UPSEAT 2002]

• A.             \[3v\cos \theta \]
• B.               \[2v\cos \theta \]
• C.             \[\frac{3}{2}v\cos \theta \]
• D.               \[\frac{\sqrt{3}}{2}v\cos \theta \]