JEE Main 2020 (4 Sep, Shift 2) Physics Q8: Two identical…

Question

Two identical cylindrical vessels are kept on the ground and each contain the same liquid of density d. The area of the base of both vessels is S but the height of liquid in one vessel is

x_1

and in the other,

x_2

. When both cylinders are connected through a pipe of negligible volume very close to the bottom, the liquid flows from one vessel to the other until it comes to equilibrium at a new height. The change in energy of the system in the process is :

(1) $\frac{3}{4}\,gdS\,(x_2-x_1)^2$
(2) $gdS\,(x_2^2+x_1^2)$
(3) $gdS\,(x_2+x_1)^2$
(4) $\frac{1}{4}\,gdS\,(x_2-x_1)^2$ Official answer

Official answer

Option 4

NTA final key (Sep 2020).

Accepted Answer

Option 4: $\frac{1}{4}\,gdS\,(x_2-x_1)^2$

Answer

$\frac{3}{4}\,gdS\,(x_2-x_1)^2$

Answer

$gdS\,(x_2^2+x_1^2)$

Answer

$gdS\,(x_2+x_1)^2$

Answer

$\frac{1}{4}\,gdS\,(x_2-x_1)^2$

JEE Main 4 September 2020, Shift 2, Physics Q8