Concept explainers
(a)
The values of
(a)
Answer to Problem 57PQ
The values of
Explanation of Solution
Write the equation of angular speed of the wheel.
Here,
Write the expression for angular velocity.
Here,
Compare equation (I) and (II).
Conclusion:
Substitute
Substitute
Take natural logarithms on both the side of the equation.
Therefore, the values of
(b)
The magnitude of the
(b)
Answer to Problem 57PQ
The magnitude of the angular acceleration of the disk at
Explanation of Solution
Write the expression for angular acceleration.
Here,
Substitute equation (III) in the equation (IV).
Conclusion:
Substitute
Write the magnitude of the angular acceleration.
Therefore, the magnitude of the angular acceleration of the disk at
(c)
The revolution of the disk during the time interval
(c)
Answer to Problem 57PQ
The revolution of the disk during the time interval
Explanation of Solution
Rewrite the expression (II) for angular displacement.
Here,
Integrating the equation (VI) using the limits.
Substitute equation (III) in the above equation.
Conclusion:
Substitute
Convert the radians to revolutions.
Therefore, the revolution of the disk during the time interval
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Chapter 12 Solutions
Physics for Scientists and Engineers: Foundations and Connections
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