Sampling: question regarding sampling period what exactly happens when I increase the sampling period ?

Providing some Matlab plots so that I can be more clear.

Using the signal $x(t) = \sin(10\pi t)$ and periods $T_s=0.02 ,\; 0.05 ,\; 0.1$







What happens exactly to the signal when the $T_s = 0.1s$ ?
You sample at times $nT_s$, so the values of the sampled signal are

$$x_d[n]=x(nT_s)=\sin(10\pi nT_s)\big |_{T_s=0.1}=\sin(n\pi)=?$$

Can you take it from here?