Light is incident normally on a diffraction grating through which the first order diffraction is seen at $32°$ . The second order diffraction will be seen at

$\theta ={32}^0$

For grating $(e+d)\sin {\theta }_n=n\lambda$

$(e+d)\underset{ }{\to }$grating element

$\sin {\theta }_n=\frac{n\lambda }{(e+d)}$

If n=1 , $\sin {\theta }_1=\frac{\lambda }{(e+d)}=\sin {32}^0=0.53$

If n=2 , $\sin {\theta }_2=\frac{2\lambda }{(e+d)}=2\sin {32}^0=1.06$

Since the sine of any angle cannot be greater than 1, therefore there is no second order diffraction.