A U-tube filled with water accelerates horizontally with acceleration $a$. Find the height difference $\Delta h$ between the liquid levels in the two vertical limbs separated by distance $L$.
2.
Two soap bubbles of radii $r_1$ and $r_2$ ($r_1 > r_2$) coalesce under isothermal conditions to form a common interface. Find radius of curvature of common surface.
