If z is a complex number satisfying $z^4+z^3+2z^2+z+1=0$ , then  $\left|z\right|$ is equal to

$z^4+z^3+2z^2+z+1=0$ 

$\Rightarrow (z^4+z^3+z^2)+(z^2+z+1)=0$

$\Rightarrow z^2(z^2+z+1)+(z^2+z+1)=0$

$\Rightarrow (z^2+1)·(z^2+z+1)=0$

$\Rightarrow z^2+1=0or{z}^2+z+1=0$

$z^2=-1or{z}^2+z+1=0$

$z=\pm 1,\omega ,{\omega }^2$

$\left|z\right|=1$