Battery stall

How to make a collection of batteries out of only one battery? We will need a glass and a rectangular aquarium.

A battery in a glass full of water seems to be wider. In order to make it thinner we have to place an empty glass with a battery inside to an aquarium filled with water. Isn't that simple?

The ability of an optical apparatus to magnify depends not only on the shape and the material of the object, but also on the medium in which the apparatus operates. Your eye works properly in the air, but in water the image is blurred - the lens of the eye cannot focus well enough.

The air bubbles in this glass ashtray work like a reducing lens.