The rate of rotation of most pulsars gradually decreases because rotational kinetic energy is gradually converted into other forms of energy by a variety of complicated friction process.
Suppose a pulsar of mass 1.5x10^30 kg and radius 20km is spinning at the rate of 2.1 rev/s and is slowing down at the rate of 1x10^-15 rev/s.
A) What is the rate in J/s at which the rotational energy is decreasing?
B) If the rate of decrease is constant, what how long will it take the pulsar to come to a stop?