• A crane hoist is required to raise 300 kg weight at a speed of 0.40 m/s.
• The hook is mounted on a block that carries a single pulley sheave.
  One end of the hoisting cable is anchored on the crane trolley and the other is wound up on a winch drum 0.30 m in diameter.
  The drum is driven by a speed-reducing gear of a 45:1 ratio. The whole mechanism may be considered to be 65% efficient.
  Determine the power and speed rating of the motor and the braking torque exerted by the motor when it lowers the load at a rate of 0.5 m /s.
  
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