Work, energy, and power problem

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The discussion centers on calculating various physics parameters for the Queen Mary 2 (QM2), a cruise ship with a mass of 150,000 gross tons and a maximum power rating of 117 MW. The kinetic energy of the QM2 at a speed of 15.0 m/s is calculated to be 1.71 x 1010 Joules. The work done by the ship's motors to accelerate from 0 to 15 m/s is equal to this kinetic energy, also 1.71 x 1010 Joules. The minimum time required for this acceleration, ignoring drag, is calculated to be approximately 9.18 x 1014 seconds. The force exerted by the ship's propellers at this speed remains unresolved in the discussion.

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1. The Queen Mary 2, whose maiden voyage was in January 2004, is a cruise ship that has a mass of 150,000 gross tons (which equals 1.52×108 kg, about three times that of the Titanic). Her electrically driven pod motors have a maximum power rating of 1.57×105 hp, or 117 MW. (a) What is the kinetic energy of the QM2 when she is moving at 15.0 meters/second? (b) What is the work done by the ships motors to accelerate the ship from 0-15m/s. (c) Find the absolute minimum time in which the ship's engines could accelerate her from rest up to 15.0 m/s. Ignore the drag resistance of the water, air, and so on. (d) What is the force that the ship's propellers exert on the water when the Queen Mary 2 is moving at 15.0 m/s (assume that the maximum power is used)?

attemps-
a-ke= 1/2 m v^2
ke= 1.71 x 10^10

b= w= ke
w= 1.71 x 10 ^10

c- p= w/t
1.57 x10 ^5= 1.71x 10^10 t
t= 9.18128655 x10 ^14

d- no idea.
 
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