Answer :
Final answer:
When a capillary tube is lifted above the water reservoir, the water level inside remains unchanged due to capillary action, governed by the surface tension and the cohesive and adhesive forces, not by the tube's position relative to the reservoir. Therefore the correct answer is C
Explanation:
When a 10cm long capillary tube, with 2cm of capillary rise, is lifted 5cm above the water reservoir, the water within the tube does not flow back into the reservoir nor does it move higher or split within the tube. Instead, the water level would remain essentially unchanged at the 2cm rise. This phenomenon occurs because capillary action is determined by the interaction between the cohesive forces of the water molecules themselves and the adhesive forces between the water molecules and the walls of the capillary tube, not by the relative position of the tube to the water reservoir.
Moreover, the quantity of water that the capillary action can pull up and hold against gravity is determined by the diameter of the capillary tube and the properties of the liquid, such as its surface tension and the angle of contact with the tube's material. Therefore, lifting the tube merely separates the water column from the reservoir but does not affect the height of the water column maintained by capillary action within the tube itself.
