Physics
A drop of liquid assumes spherical shape because:

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

ANSWER DOWNLOAD EXAMIANS APP

Physics
On a cold day when the room temperature is 15°C, the metallic cap of a pen becomes much colder than its plastic body, though both are at the same temperature of 15°C, because :

Metals have higher thermal capacity than plastics
Plastics have a higher thermal conductivity than metals
Plastics have a lower density than metals
Metals are good conductors of heat

ANSWER DOWNLOAD EXAMIANS APP