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The propeller on a boat motor is initially rotating at 8 revolutions per second. As the boat captain reduces the boat speed, the propeller SLOWS at a steady rate of 0.9 revolutions per second per second. After 17 revolutions, how fast is the propeller spinning in revolutions per second

User JHH
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1 Answer

5 votes

Answer:
5.77\ rps

Step-by-step explanation:

Given

Initial angular velocity is
\omega_i=8\ rps

rate of reduction
\alpha=0.9 rev/s^2

after 17 revolution i.e.
\theta =17\ rev

using
\Rightarrow \omega_f^2-\omega_i^2=2\alpha\theta

Insert the values


\Rightarrow \omega_f^2=8^2-2* (0.9)*17\\\Rightarrow \omega_f^2=33.4\\\Rightarrow \omega_f=5.77\ rps

User Jack C
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