Answer :
When the radius of a capillary tube is doubled, the mass of water in the tube quadruples because the height of the water remains the same, while the cross-sectional area increases by a factor of four.Hence,option D is correct,4M.
The student's question deals with the concept of capillary action in physics and how changing the radius of a capillary tube affects the mass of water that the tube can raise. In the given scenario, the radius of the capillary tube is doubled. According to the principles of capillary action, the height to which water rises in a capillary tube is inversely proportional to the tube's radius, a relationship derived from the Jurin's Law.
However, the mass of the water that can be held within the tube depends on both the height and cross-sectional area. Since the tube's radius is doubled, its cross-sectional area, which is proportional to the square of the radius (Area \\= \\pi R^2), will increase by a factor of four.
Given that the height does not change due to the mass continuity of water and is still being drawn to the same maximum height by capillary action, the mass of water in the tube will therefore be four times greater. Therefore, when the radius of the capillary tube is doubled, the correct answer is D. 4M.
Hence,option D is correct,4M.
