Final answer:
The angular velocity of the wheel before it was unplugged is 0.500 rad/s. The time it takes for the wheel to come to a complete stop is 77.46 seconds. The wheel makes 38.76 turns before coming to rest.
Step-by-step explanation:
The question asks about the angular velocity and the time it takes for a jeweler's polishing wheel to stop rotating after it is unplugged. The angular velocity of the wheel before it was unplugged is 0.500 rad/s. The time it takes for the wheel to come to a complete stop is given as 77.46 seconds.
We can use the formula:
Angular acceleration = (final angular velocity - initial angular velocity) / time
Substituting in the given values:
Angular acceleration = (0 - 0.500) / 77.46 = -0.00645 rad/s²
This negative value indicates that the wheel is slowing down.
To find the number of turns the wheel makes before coming to rest, we can use the formula:
Number of turns = (initial angular velocity)^2 / (2 * angular acceleration)
Substituting in the given values:
Number of turns = (0.500)^2 / (2 * -0.00645) = 38.76 turns