Answer :
Final answer:
Water cannot come out of a capillary tube dipped in it due to capillary action, a phenomenon where water rises against gravity within the tube due to adhesive and cohesive forces. The height the water reaches depends on the tube's diameter and the water's surface tension. This principle is vital in both scientific applications and natural processes.
Explanation:
When a capillary tube is dipped in water, water cannot come out of the tube, irrespective of its length, due to a phenomenon known as capillary action. This process originates from the combination of the liquid's adhesive forces to the tube and the cohesive forces within the liquid itself.
A notable aspect of capillary action is how it allows the liquid to rise against gravity. When the tube's small diameter interacts with water, a liquid that wets the tube's surface, the water is drawn up, creating a curve known as a meniscus. This curvature results from water molecules being more attracted to the glass tube's material than they are to each other, hence clinging to it and rising along the tube's interior.
The height to which water climbs in a capillary tube depends on several factors including the tube's diameter, the liquid's surface tension, and the contact angle between the liquid and the tube's surface. For water in a glass tube, its strong adhesion to glass causes it to rise up inside the tube until gravitational forces balance the upward capillary force.
It is also interesting to note that the smaller the diameter of the tube, the higher the water can climb. This phenomenon not only is observable in laboratories but also plays essential roles in nature, such as in the transportation of water from roots to leaves in plants.