The angular acceleration and period of a pulsar

AI Thread Summary
The discussion focuses on calculating the angular acceleration and period of a pulsar using the formulas T = 2π/ω and ω = 2π/T. The calculated angular acceleration is α = -2π/(2.94*10^-15)^2, resulting in a value of 7.27*10^29 rad/s². Participants express confusion about representing an indefinitely increasing period and the implications of a constant angular acceleration. Clarifications are provided on the need to assume constant angular acceleration to determine when angular speed reaches zero and to backtrack to find the initial angular speed and corresponding period. The conversation emphasizes careful substitution and understanding of the formulas involved.
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Homework Statement
A pulsar is a rapidly rotating neutron star that emits a radio beam the way a lighthouse emits a light beam. We receive a radio pulse for each rotation of the star. The period T of rotation is found by measuring the time between pulses. Suppose a pulsar has a period of rotation of T = 0.0178 s that is increasing at the rate of 9.27 x 10-8 s/y. (a) What is the pulsar's angular acceleration ? (b) If is constant, how many years from now will the pulsar stop rotating? (c) Suppose the pulsar originated in a supernova explosion seen 1160 years ago. Assuming constant \alpha , find the initial T
Relevant Equations
T=\frac {2\pi}{\omega}
for (a) ##T=\frac {2\pi}{\omega}##
$$\omega=\frac {2\pi}{T}$$
$$\frac{d \omega}{dt}=\frac {-2\pi}{T^2} \frac {dT}{dt} $$
$$\alpha=\frac {-2\pi}{(2.94*10^-15)^2} = 7.27*10^29 rad/s^2$$

for (b) I'm understand that it's infinity, because the period is increasing indefinitely, so it's slowing down forever.
But I don't know how to express that in formula, and infinity is not something I can input in the homework software.
So I must be wrong about it, but don't know how to get the correct answer.

(c) I don't have anything here.
 
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a is wrong - do your substitution more carefully.
In b they are asking you to assume the angular acceleration is constant - not dT/dt. If you have a constant negative α, and know the angular speed now, you can work out when the angular speed becomes zero.
For c you can likewise work backwards and calculate what the angular speed was initially, then convert that to a value of T.
 
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