Question

When we insert a jar into a bucket completely filled with water, some water spills out. why?

Answer 1

The bottle which you consider yo be empty is actually full of air. And air occupies space so when you submerge an empty bottle upside down in a tub of water, the air gets trapped into it as it have no space to come out. Since the space is occupied by air, water can not enter it but when you tilt the bottle the air comes out and bubbles are created and the empty space inside the bottom gets filled with water.

Answer 2

Bcz the jar takes the intercellular space of the water due to which the molecules donot get space to stay and they get out of. Bucket