A jet of water with cross section of $6$ $cm^2$ strikes a wall at an angle of $60^o $ to the normal and rebounds elastically from the wall without losing energy. If the velocity of the water in the jet is $12$ $m/s$, the force acting on the wall is ....... $N$
  • A$0.864$
  • B$86.4 $
  • C$72 $
  • D$7.2$
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