Water waves of wavelength are incident normally on an obstacle with a narrow gap. The widthof the gap is equal to. The waves from the gap emerge over an angle, as shown.incidentwater wavesemergingwater wavesThe gap is slowly widened.Which changes, if any, occur to and to the wavelength of the emerging waves? wavelengthA decreases remains the sameB increases remains the sameC remains the same decreasesD remains the same increases

The phenomenon described here is diffraction, which is the bending of waves around obstacles or the spreading of waves by passing them through an aperture or opening.

When the width of the gap is equal to the wavelength of the waves, the waves spread out in all directions after passing through the gap. This is known as diffraction.

As the gap is widened, the amount of diffraction decreases. This means that the waves spread out less, and the angle θ decreases.

The wavelength of the waves, however, is not affected by the width of the gap. The wavelength is a property of the waves themselves and does not change unless the waves interact with a medium that changes their speed.

So, the correct answer is A: θ decreases and the wavelength remains the same.