The U-tube shown below is immersed in hot water. X and Y are the red ink droplets present inside the tube. What will you observe after some time?

When a U-tube containing red ink droplets (X and Y) is immersed in hot water, several observations can be made over time due to heat transfer and fluid dynamics:

1. Movement of Ink Droplets: The heat from the hot water will increase the temperature of the liquid inside the U-tube. As the temperature rises, the viscosity of the liquid may decrease, allowing the ink droplets to spread or move more freely within the liquid.

2. Diffusion: The hot water may cause the ink to diffuse more rapidly, causing the red ink droplets to disperse and spread throughout the liquid. This diffusion is driven by the thermal energy that increases molecular movement.

3. Color Change in Regions: After some time, the regions around the ink droplets will change color as the ink disperses into the surrounding liquid, leading to a more homogeneous mixture.

4. Possible Convection Currents: If the temperature difference is significant, it could create convection currents within the liquid. These currents can further facilitate the mixing of the ink and the liquid, enhancing the dispersion process.

Overall, after some time, you will observe that the red ink droplets become less concentrated and more evenly distributed throughout the liquid in the U-tube due to the combined effects of diffusion and possibly convection currents caused by the heat from the surrounding hot water.