Plane microwaves are incident on a slit of width  5.0 cm, if first diffraction minimum is formed at an angle  θ=30∘, then what is the wavelength of the microwaves?

GivenWidth of the slit  b=5.0 cmFirst diffraction minimum is formed at  θ=30∘For the diffraction minima,We have  bsinθ=nλ⇒sinθ=λb For the first minima, we put n=1 ⇒sin⁡30=λ5⇒λ5=12⇒λ=52=2.5cm