Concept explainers
(a)
The rotation rate after the glitch.
(a)
Answer to Problem 15PQ
The rotation rate after the glitch is
Explanation of Solution
From Example 12.2, it is found that the original rotation rate is
Write the expression for the rotation rate after the glitch.
Here,
It is given that the fractional increase in rotation rate is,
Solve equation (II) for
This shows that the rotation rate after the glitch is almost equal to the original rotation rate since the change is negligibly small compared to the original rate. Thus, substituting
Conclusion:
Therefore, the rotation rate after the glitch is
(b)
The new
(b)
Answer to Problem 15PQ
The new angular acceleration is
Explanation of Solution
From Example 12.2, it is found that the magnitude of original angular acceleration is
Write the expression for the angular acceleration after the glitch.
Here,
It is given that the fractional increase in angular acceleration is,
Solve equation (II) for
Conclusion:
Substitute
Therefore, the new angular acceleration is
(c)
The time taken for the pulsar to return to its pre-glitch rotation rate.
(c)
Answer to Problem 15PQ
The time taken for the pulsar to return to its pre-glitch rotation rate is
Explanation of Solution
It is obtained that the angular acceleration after the glitch is
Write the expression for the angular frequency in term of the angular acceleration.
Here,
Solve equation (VIII) for
Multiply and divide the right-hand side of equation (IX) by
Conclusion:
Substitute
Therefore, the new angular acceleration is
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Chapter 12 Solutions
Physics for Scientists and Engineers: Foundations and Connections
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