91Ó°ÊÓ

The time period of rotation of the Pulsar,${\text{P}}_t=5578064487275ms$

The uncertainty per rotation is$Â\pm 3×{10}^{-17}s$

Pulsars are rapidly rotating stars that emit radio pulses with a very regular frequency.Atomic clocks measure time by measuring the frequency of radiation emitted by atoms.An atom's natural oscillations work like the pendulum in a grandfather clock.

The frequency is reciprocal of time. Therefore,

$\text{f=}\frac{1rotation}{1.55780644887275×{10}^{-3}s}$… (i)

Multiply this frequency by the given time 7days in seconds to get the number of rotations.

Thus, the Pulsar makes$3.88×{10}^8$rotations in 7 days.

Using equation (i), time is calculated as:

$n=f×t$

Here number of rotations is $1×{10}^6$. So

Thus, the time taken by the Pulsar to rotate one million times is$\text{1557.80644887275s}$

The time uncertainty per revolution is$Â\pm 3×{10}^{-17}s$

For one million revolutions, associated uncertainty is,

role="math" localid="1651834524162" $$\begin{gathered} \text{Associated Uncertainty}=Â\pm 3×{10}^{-17}×1×{10}^6 \\ =Â\pm 3×{10}^{-11}\text{s} \end{gathered}$$

Thus, the associated uncertainty is.${\text{±3×10}}^{-11}s$