Explain whether the water wave produced is longitudinal or transverse. The circular lines represents the crests of the wave. On Fig. 4.1, indicate one wavelength. Fig. 4.2 shows a plane barrier placed at an angle to straight wave fronts. State what will happen when the wave fronts hit the barrier.

Water waves on the surface are primarily transverse waves.

In a transverse wave, the particles of the medium (water) oscillate perpendicular to the direction of wave propagation. For water waves, water particles move up and down, while the wave energy travels horizontally outwards.

A wavelength is the distance between two consecutive crests of a wave.

4.1.
On Fig. 4.1, the circular lines represent the crests of the wave. The distance between any two adjacent circular lines represents one wavelength.

When the wave fronts hit the barrier, reflection occurs.

The wave fronts will reflect off the plane barrier, changing their direction of propagation. The angle of incidence of the incoming waves will be equal to the angle of reflection of the outgoing waves.