Question: Problem 3 : Propeller coming to rest ( 1 0 points ) A motor is used to spin a submerged propeller that has two blades.

Problem 3: Propeller coming to rest (10 points)
A motor is used to spin a submerged propeller that has two blades. When the motor is running, the propeller spins with a constant angular velocity \(\omega_{i}=18.9\mathrm{rad}/\mathrm{s}\) in the counterclockwise direction. At some moment of time, the motor shuts off. Suppose that the surrounding water exerts a constant drag force of magnitude 5.00 N on each blade, perpendicular to each blade and opposite the direction of rotation, at a point 0.500 m from the pivot. The moment of inertia of the propeller is \( I=198\mathrm{~kg}\cdot \mathrm{~m}^{2}\). You can neglect gravity in this problem, (See diagram below.)
Hint: Pay careful attention to the signs of your answers in parts (a)-(b).
(a) What is the net torque on the whole propeller?
\(/2\)(b) What is the angular acceleration of the propeller?
/2.(c) What is the net work done by the surrounding water on the propeller as it comes to rest? Hint: The answer is negative and can be found without solving (a) and (b) using a certain theorem that we covered in class. A second way to solve this problem makes use of (a),(b), and a bit more.
(d) How much time does it take for the propeller to come to rest? If you did not solve part (b), you may assume that the angular acceleration is \(\alpha=-1.00\mathrm{rad}/\mathrm{s}^{2}\) for full credit on this part.
Bonus: When the motor is running, what power is the motor delivering to the propeller? \( P=\tau \omega \)
Problem 3 : Propeller coming to rest ( 1 0 points

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