Physics
A drop of liquid assumes spherical shape because:

A sphere has the largest surface area for a given volume
Inter molecular forces are weak in liquids
Intermolecular forces are strong in liquids
A sphere has the least surface area for a given volume

ANSWER DOWNLOAD EXAMIANS APP

Physics
Siphon will fail to work if:

Both its limbs are of unequal length.
The temperature of the liquids in the two vessels are the same.
The level of the liquid in the two vessels are at the same height.
The densities of the liquid in the two vessels are equal.

ANSWER DOWNLOAD EXAMIANS APP