$-$ Your answer is partially correct.

Particles pass through a single slit of width $1\mathrm{.}6$ mm $($see Figure $29\mathrm{.}15).$ The de Broglie wavelength of each particle is $644$ nm $.$ After the particles pass through the slit, they spread out over a range of angles. Assume that the uncertainty in the position of the particles is one$-$half the width of the slit, and use the Heisenberg uncertainty principle to determine the minimum range of angles.

$\backslash [$

$\backslash$theta$=$

$\backslash ]$