Cohesion, Adhesion, and Refraction

Cohesion: Water molecules beneath the surface area of the water exert a stronger force than do the air molecules above. This causes the surface area of the water to be minimized, resulting in the formation of streams and droplets. Adhesion: The streams of water flowing down the side of the glass form because of attractive forces between the water molecules and the glass, which work against the forces of gravity. Refraction: Light rays pass from one medium into another in which the speed of light is different, causing the thumb to appear bent and broken in places.