the force acting required to tow a boat at constant velocity is directky proportional to speed...if a speed 4 km/hr,corresponding power is 7.5kw....how much power is neede for speed=12km/hr?

Dear shivanshi

given

F= α V

power P = FV

            =α V²

      7.5  =α * 16

        α   =7.5/16

so at 12 km/hr

   P = α * 144

       =7.5/16   * 144

       =67.5 kw

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